Cannabis Botany Basics
Contents
Categorizing the Cannabis Plant
Ruderalis Hybrids, THC or CBD dominant vs Balanced Strains
Humidity and Temperature Measurement Tools
Nutrient Deficiencies, Toxicity and Remedies
EC Meters (electric conductivity)
Germination: Cup of Water to Paper Towel
Top ten tips for successful vegging:
Cannabis Flowering Stage Timeline
Disinfection, Sanitizing, and Sterilization
Cannabis Botany Basics
Categorizing the Cannabis Plant
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There are three categories when it comes to the Cannabis family. Many people classify them based on their effects and growing traits, but there is no scientific evidence to prove sativas create uplifted, euphoric effects while indicas create a sedating or a physical relaxed effect.
“The clinical effects of the cannabis chemovar have nothing to do with whether the plant is tall and sparse vs. short and bushy, or whether the leaflets are narrow or broad.”
Ethan Russo, a neurologist and cannabis researcher
The words “indica” and “sativa” were introduced in the 18th century to describe different species of cannabis: Cannabis sativa and Cannabis indica. Cannabis Ruderalis is a recent addition.
Sativa
The term sativa, named by Carl Linnaeus, described hemp plants found in Europe and western Eurasia, where it was cultivated for its fiber and seeds.
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Tall Stature,
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Longer flowering cycles,
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Narrow Leaves, and
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Better suited for warmer, longer season climates.
Indica
The term indica, named by Jean-Baptiste Lamarck, describes the psychoactive varieties discovered in India, where it was harvested for its seeds, fiber, and hashish production.
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Short in stature,
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Shorter flowering cycles,
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Suitable for colder climates with shorter seasons, and
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Broad leaves.
Ruderalis
Cannabis Ruderalis is also known as an “auto-flowering strain.” Its flowering cycle is based on the time since its shell cracked; generally these types begin flowering after 21-35 days of vegetative growth. It generally sits between 1-2.5’ (30-76cm) tall at harvest, with a rugged and shaggy growth pattern which produces buds tending to be small but still relatively chunky. Cannabis ruderalis naturally has low concentrations of THC. However, the stability and short lifecycle make ruderalis versatile and attractive to breeders who want to take advantage of breeding a hybrid with the advanced potency and flavor profile from its genetic partner.
Hybrids, THC or CBD dominant vs Balanced Strains
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Hybrids: strains where growers have cross-bred species to bring out the best in both. Many people will argue thanks to years of crossbreeding, there are no “true” Sativas or Indicas. Currently if a strain is labelled a hybrid, it is being marketed as a strain balancing the positive effects of its parentage, be it any mix of Sativa with an Indica strain.
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THC-Dominant Strains: these strains are selected for their high THC content and intoxicating/ euphoric effects. These strains are used to deal with several medical symptoms including pain, insomnia, lack of appetite, etc.
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CBD-Dominant Strains: strains contain only small amounts of THC and are widely used by those overly sensitive to THC or patients needing clear-headed symptom relief.
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THC/CBD Strains: a balanced strain offering patients a balance of both desired effects and symptom relief with a clear-headed high. Good choice for new consumers
Top known strains for:
Sativa
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Jack Herer
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Amnesia Haze
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Strawberry Cough
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Lemon Haze
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Super Silver Haze
Hybrid
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White Widow
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AK-47
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Blueberry
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Pineapple Express
Indica
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Northern Lights
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OG Kush
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Purple Kush
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Granddaddy Purp
CBD
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Harlequin
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Ringo's Gift
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Charlotte's Web
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ACDC
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Harle-Tsu
CBD
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Sweet & Sour Widow
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OG Kush CBD
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Harlequin
Cannabinoids and Terpenes
Cannabinoids
Cannabinoids: Cannabinoids are the chemical compounds of the cannabis plant which influence the human body when the plant is consumed. These compounds bind to the CB1 and CB2 receptors in the endocannabinoid system. These cannabinoids have a variety of effects and healing properties depending on which terpene or other cannabinoid it is paired with. There are over 120 Cannabinoids discovered to this day. Here are the main studied cannabinoids:
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THC (tetrahydrocannabinol): makes us feel hungry and high. Relieves symptoms like pain and nausea.
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THCA (tetrahydrocannabinolic acid): Anti-inflammatory, neuroprotective, anti-emic, and anti-proliferative.
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THCV (tetrahydrocannabivarin): is an appetite suppressant, helps with Alzheimer’s and Diabetes, reduces panic attacks, and stimulates bone growth.
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CBD (cannabidiol): is a non-intoxicating compound known to alleviate anxiety, pain, inflammation, and many other medical ailments.
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CBDA (cannabidiol acid): Anti-inflammatory, anti-nausea, antioxidant, anti-proliferative, and antibacterial.
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CBN (cannabinol): is a psychoactive cannabinoid, it is a result of the degradation of THC from either heat or time.
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CBG (cannabigerolic): is also known as the grandfather cannabinoid. THC and CBD to name a few are created from CBG.
Terpenes
Terpenes are aromatic compounds commonly produced by plants. They can be found in hops, peppers, lavender, flowers, oranges, and of course, cannabis. Secreted by the same glands which produce THC and CBD (trichomes), terpenes are what makes up cannabis’ smell and taste. Pairing certain terpenes and cannabinoids can offer an entourage effect.
“Terpenes seem to be major players in driving the sedating or energizing effects.”
- Jeffrey Raber, Founder of the Werc Shop
Plant Grow Basics
A plant needs 3 basic things to grow: As you maximize what the plant needs you will maximize the yield. Different plants will have their own unique combination of these:
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Photons: Also referred to as energy given off by a light or sunlight. Photons are needed (as you may remember from Grade Seven science) for plants to convert nutrients into useful energy through the process of photosynthesis.
A photon is a tiny particle of electromagnetic radiation. A particle that makes up light. The process of photons breaking down chemical bonds is the driving force behind photosynthesis.
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Water: Whether in the soil or in a hydroponic grow.
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Environment: This concerns not just the growing medium (soil versus hydroponics, for example), but indoor versus outdoor growing, nutrients, pests and diseases to name a few.
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Photosynthesis
Photosynthesis is used by plants and other organisms to convert light energy into chemical energy which can later be released to fuel the organisms' activities. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water.
Indoor Grow lights
Indoor growing success comes down to the quality of supplemental lights offered by the grower. There are four choices when it comes to indoor grow lights: Incandescent, CFL, HID (HPS/MH/CMH), and LED.
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NOTE: Lighting should be your biggest expense. By having the quality light cannabis plants need, you will be increasing potency, weight, and yields!
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Incandescent
This is the least favorable option as its low efficiency for plant growth is due to lacking the blue wavelengths.
CFL
Originally developed in the late 1800s, it did not become favorable until the mid-1970s. Efficiency rated between 7-10%. They emit low heat for easy close placement of plants. Available in single bulbs or one to four-foot strip lights. CFL are affordable and use one-fifth of the power of traditional bulbs. Great for nurseries, seedlings, young plants, and houseplants.
HID (HPS/MS/CMH)
Developed in the mid 1950’s, they emit higher volumes of wavelengths and energy, allowing distances between the canopy of the plants and the light fixture. Downside, they emit heat usually requiring venting to reduce heat stress. The initial cost is more than CFL but are used for fruiting plants.
Metal Halide (MH) is typically used for vegetative grow cycles, where High Pressure Sodium (HPS) bulbs are used for flowering stages. Ceramic Metal Halide (CMH) is more efficient than a basic MH bulb, and is used similarly to an HPS bulb. However, CMH, while less expensive, is less efficient than an HPS bulb (and may be limited in the wattage of fixtures).
LED
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LED was developed in the mid-20th Century and has rapidly evolved since the 1990 to the point they are now used for plant growth. LEDs are by far the most efficient when it comes to energy use, with efficiency rates of 21%. Lifespans of LEDs compared to CFLs are six to seven times longer. They emit low heat and allow distance between plants and the light fixture. Originally, costs for LED lamps where expensive, but (as of 2020) it is now one of the cheapest lighting systems.
Lighting Tips
Lighting for Plants, or “Lumens are for Humans”
Lumens measure “luminous flux” or how bright a light is to the human eye. The amount of light received at a location is known as lux, or lumens per square meter. One lux(lx) is equal to one lumen (lm) per square meter:
1 lx = 1 lm/m2
1000 lumens, shining uniformly on an area of 1 square meter will illuminate the area with an illuminance of 1000 lux. If you spread that light over 10 m2, the same 1000 lumens will give a reduced illuminance of only 100 lux.
Lux is the light level at a surface. If you think of a light bulb, the lux will vary with the distance from the light source because the light spreads out.
Lumens are a great way to compare the amount of light put out by fluorescent lights, CFLs, HIDs, MH and HPS grow lights. However, when it comes to LED grow lights, LEDs usually give off light only in very narrow wavebands of light which is undetectable by a lux meter.
PAR (Photosynthetically Active Radiation): Instead of considering how much light is produced from a light source as humans see it, PAR actually considers only the spectral range of solar radiation from 400 to 700 nm, which is the spectra of light that plants can use for photosynthesis(blue and red spectra). Use a PAR meter to measure how well your lights are covering your grow footprint and adjust your light setup accordingly.
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How to accurately measure Wattage for your room:
Watts per square foot/meter squared (wattage WILL vary by light source):
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Minimum: 30w per sq ft./ or 323w per m2
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Mid-Range: 30-50w per sq ft./ or 323-538w per m2
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Optimal Range: 50-80w per sq ft./ or 538-861w per m2
Environmental Control
Choosing the appropriate environmental set-up will determine the success of your grow. This includes gas exchange with Carbon Dioxide (CO2) and Oxygen (O), humidity, temperature, odour control, grow systems, nutrients, and the tools used to monitor the environment.
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Gas exchange
The process of photosynthesis takes water, CO2, and light energy to produce energy for cell production and oxygen for the environment. Just like the plants natural energy production being so crucial on its chance of survival, indoor environmental control is just as critical for the success of the grower. Gardening indoors requires the grower to reproduce “Mother Nature’s” effects of light, air circulation, CO2 availability, and nutrient requirements.
Carbon Dioxide is especially important for optimal plant health. CO2 can increase yields by up to 30%. Plants grown with elevated CO2 levels are also better at resisting diseases and insects. CO2 products come in a variety of systems, anywhere from mushrooms bags to CO2 machines.
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Humidity
Humidity is the amount of water vapor in the atmosphere. Water vapor is the invisible presence of water in its gaseous state. Humidity is a significant aspect of the atmosphere because it affects the weather and the climate.
Temperature
Cannabis likes a comfortable room temperature (or slightly warmer) when growing indoors; and for the atmosphere to be not too dry, not too humid. Cannabis plants prefer temperatures in the 70-85°F (20-30°C) range during the day when the lights are on. When lights are off (or at night), cannabis plants are happy with slightly cooler temperatures.
Vegetative Stage: Young growing cannabis plants in the vegetative stage prefer temps a bit warmer than in the flowering stage, in the 70-85°F (20-30°C) range.
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Flowering Stage: In the flowering stage (when cannabis plants start making buds), it is best to keep temperatures slightly cooler, around 65-80°F (18-26°C) to produce the best color, trichome production and smell. There should be a 10-degree difference between night and day temps for the best results (this is especially important in the flowering stage for highest quality bud development).
In the winter you may need to incorporate a portable heater to the room to maintain temperatures. Conversely, during the summer months some growers experience their rooms becoming too warm, in which an air conditioning unit will need to be added.
Humidity and Temperature Measurement Tools
Humidistat and Thermostat: These devices are used to dial in and control the temperature and humidity in the garden. Based on the temperature and humidity level a grower has set, these devices cycle on or off exhaust fans, heaters, humidifiers, and dehumidifiers to maintain a set temperature and humidity.
Humidifier/Dehumidifier: A humidifier and dehumidifier are intended to be used in the garden to control humidity levels.
Thermometer and Hygrometer: These devices are used to indicate what the temperature and humidity levels in the grow are. Utilizing more than one of these devices in a grow area will allow you to get precise readings on the overall health of the grow environment. Ideally, these devices are hung above the light, top of the growth canopy, and below the growth canopy.
To control high temperatures and humidity in rooms, install an exhaust system for maximum control. This setup will require an exhaust/ intake fan. For continuous air flow amongst the plants, having an oscillating fan on 24/7 in your room guarantees the plants are getting optimal air flow to the stomata under the leaves.
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Temperature is also incredibly important to the drying and curing process, and a professional dry/ cure is one of the biggest factors when it comes to producing top-shelf bud.
Odour Control: Using an exhaust fan attached to charcoal filter to scrub the air of odours exiting the grow tent. If an intake fan is used, it should have a HEPA filter attached to eliminate any unwanted pests and mold spores from entering your grow tent/area. Other methods for small area smells are Ona Blocks and deodorizers.
Growing Environment
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Grow systems include growing in soil and pots, using a hydroponic system, or assembling an irrigation system to eliminate the need of watering by hand. When beginning your first indoor garden you want to keep things simple. Using soil with pots is an ideal system for beginners. Fabric pots are highly recommended as these provide more oxygen to the root zone and help increases yield. Once you have completed your first grow you can re-evaluate if you want to upgrade to a more automatic system such as hydroponics.
Soil
You can choose premade soil mixes or create your own mixture using certain soil additives and compost teas for nutritional values. Plastic pots or fabric bags/pots are typical choices for gardens. Costs for both are similar. While plastic pots will last much longer, fabric bags/pots are better at aeration and drainage of the roots, and allow for air root pruning; all of which work to increase the yield of your crop.
Hydroponics
Hydroponics is a controlled method of growing plants by suspending the plant and roots in a water based, nutrient-rich solution. If you give the exact amount light, atmosphere, water, and nutrients, you will reach the absolute full potential of the plant. Hydroponics does not use soil, instead the root system is supported using an inert medium such as coconut husks, rockwool, clay pellets, peat moss, perlite, or vermiculite to name a few. Hydroponics allows the plants roots to come in direct contact with the nutrient solution, while also having access to oxygen, which is essential for proper growth.
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Hydroponic systems include wick systems, deep water culture, ebb and flow, drip method, nutrient-film technique, and aeroponics.
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Advantages:
Increased rate of growth which includes a greatly increased growth rate for the plants, maturation 25% faster, and producing a 30% larger crop than a soil bound plant would.
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Disadvantages:
The biggest factor for most people is cost. A quality hydroponics system of any size will cost more than its soil counterpart. As well, you must monitor and balance your pH and nutrient levels daily. The greatest risk with a hydroponics system is something like a pump failure can kill your plants within hours depending on the size of your system. Unlike soil, the growing mediums cannot store water; the plants vitality is dependent on a fresh supply of water and oxygen.
Nutrients
We have classified nutrients into three categories based on how and what the plant needs:
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Primary Macronutrients
These are nutrients required by plants in larger quantities than all other nutrients.
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N – Nitrogen: found in amino acids, nucleic acids, and chlorophyll; promote the use of carbohydrates, protein manufacturing, plant strength, and maintaining plant health.
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P – Phosphorus: major component in DNA, RNA, and ATP systems in plants, photosynthesis production, main nutrient in cell membrane development, and regulating the use of sugars and starches.
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K – Potassium: key aid in root growth, reproductive development, facilitating water usage, and helping with disease resistance and metabolizing nutrients.
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Secondary Macronutrients
These macronutrients are often used in gardening to help plants in distress while boosting their overall health and growth. An extremely important secondary macronutrient is calcium – it is ideal for the soil’s pH, which enables the plants to absorb all the nutrients in the soil. Calcium also allows the soil to become more alkaline. Similarly, magnesium is an excellent enzyme activator, which promotes botanical growth and flowering. Sulfur protects the leaves and prevents yellowing or premature aging.
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Ca – Calcium: absorption/translocation of nutrients, disease resistance, assistance in protein production, cell division and cell formation, and activation of growth-regulating hormones. Helps neutralize organic acids formed during metabolism.
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Mg – Magnesium: enzyme formation for plant development, leaf chlorophyll, and crop quality. Assists with the formation of oils, sugars, and fats.
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S – Sulfur: essential in chlorophyll, seed production, and involved in nitrogen fixation. Adds smell, colour and flavor to plants, forms a significant part of protein and amino acids.
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nts.
Micronutrients
Balanced crop nutrients means the soil and water need to have the right amounts of macronutrients AND micronutrients. One micronutrient extremely important for plant growth is boron. This directly affects germination, pollen formation, and flower retention. Iron is another micronutrient essential to healthy plant growth. This nutrient actively encourages the production of chlorophyll and prevents the leaf discoloration that is commonly found in dying plants.
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Fe – Iron: chlorophyll production, move oxygen throughout the plant.
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B – Boron: aids in germination, pollen formation, flower retention.
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Cl – Chlorine: photosynthesis production.
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Mo – Molybdenum: fixation of atmospheric nitrogen, plant growth.
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Cu – Copper: promotes healthy plant growth/health.
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Zn – Zinc: creating chlorophyll.
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Mn – Manganese: chloroplast formation, photosynthesis, nitrogen metabolism, and synthesis of enzymes.
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Ni – Nickel: metabolizes urea nitrogen.
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There are many products offering simple to complex feeding schedules. Your options are 1-part, 2-part or 3-part base nutrients to begin feeding your plant the most essential nutrients it requires. Additives/supplements can be added in small doses to correct malnutrition of micronutrients.
Nutrient Deficiencies, Toxicity and Remedies
A nutrient deficiency is the physical symptom and condition of a plant when insufficient levels of a specific nutrient or nutrients are present in the soil or growing medium.
Calcium
Deficincy Symptoms
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Upper leaf show spotting first.
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Lower leaves curl and twist.
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Yellow, brown spots appear on leaf and tips.
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Stunted growth.
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Flower development is slow.
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Brown or dark spots on leaves.
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Random pattern of spots.
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Stems start to become weak.
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Roots have little development.
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The roots begin to die in extreme cases.
Correcting Deficiency
Step 1: Flush plants-an essential step to remove any unwanted nutrients.
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Step 2: Correct pH level in water/nutrient solution.
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Step 3: Add extra calcium nutrients, a little at a time. (Dolomite lime or any bottle of Cal-Mag).
Toxicity Symptoms
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Lockout of nutrient uptake: Potassium, Magnesium, Manganese, and Iron.
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Root tips die back.
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More susceptible to heat stress.
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Showing burns on leaves (often confused with calcium deficiency).
Correcting Toxicity
Step 1: Start off by flushing your plants with pH, zero nutrient water.
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Step 2: Slowly add vegetative nutrients back into plants.
Step 3: If needed, use Calcium--low nutrients.
Nitrogen
Deficiency Symptoms
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Leaves start turning pale green.
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Red stems.
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Yellowing of the lower leaves.
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Browning of leaves.
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Yellowing of the veins of the leaf.
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Leaves drooping; looks like over-watering.
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Wilting leaves break off.
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Slow growth rate during veg. stage
Correcting Deficiency
Step 1: Start using a Nitrogen-rich nutrient. (if you haven’t already)
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Step 2: Add extra Nitrogen-rich supplements to your regular feeding cycle.
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Step 3: Add extra vegetative fertilizers in small increments.
Toxicity Symptoms
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Leaves curling downwards (nitrogen claw).
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Dark green leaves.
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Brittle stalks and stems.
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Weak Immune system.
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Easy prey for Insects.
CorrectingToxicity
Step 1: Flush your plants with pH, zero nutrient water.
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Step 2: Slowly add vegetative nutrients back into plants.
Step 3: If needed, use Nitrogen-low nutrients.
Phosphorus
Deficiency Symptoms
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Leaves turn a blue-green color.
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Lower leaves are affected first (mobile nutrient).
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Lower leaves turn yellow and brown.
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Stem can turn a purple color.
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Leaves have blotches of brown or blue.
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Slow growth.
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Affected leaves start to curl in strange shapes.
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Lower leaves begin to die.
Correcting Deficiency
Step 1: Establish optimal pH level in your water/nutrient solution.
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Step 2: Flush your plants.
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Step 3: Use a PK Booster. (Botanicare hydroplex or Canna PK 13/14)
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Step 4: Use a high Phosphorus nutrient.
Toxicity Symptoms
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New leaves show signs of yellowing from the veins outward.
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Leaf tips are slightly burned.
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Calcium and Magnesium deficiencies occur.
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Zinc and Iron deficiencies occur.
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Lower leaves curl with brown or blue spots.
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Roots start to die.
CorrectingToxicity
Step 1: Flush your plants.
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Step 2: Remove all infected and dying leaves.
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Step 3: Lower the amount of your nutrients.
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Step 4: Use a low N-P-K values Bloomers, (Fox Farms bloom) until the plant recovers.
Potassium
Deficiency Symptoms
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Stunted Growth.
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Moves from bottom of plant to top (Mobile nutrient).
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Yellow or white spots on leaves.
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Yellow, Browning or blackening of leaf tips.
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Stems become weak and brittle.
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Space between branches may increase.
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May look like nutrient burn.
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Also, resembles heat stress.
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Yellow leaves (older) bottom.
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Leaves curl under.
Correcting Deficiency
Step 1: Make sure you are using a balanced N-P-K nutrient solution for both veg and flowering.
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Step 2: Flush all plants and correct pH levels in water/nutrient solution.
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Step 3: Use a PK Booster. (Canna PK 13/13, Advanced Nutrients Hammerhead, Botanicare Hydroplex bloom).
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Step 4: Incorporate a P Booster. (Earth Juice Meta K)
Toxicity Symptoms
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New leaves show yellowing chlorosis.
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Leaf tip show some sign of burning.
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Lower leaves curl gets spots.
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Blocks the absorption of other nutrients such as calcium, magnesium, zinc, and iron.
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Grow medium becomes acidic lower than PH 5.
CorrectingToxicity
Step 1: Flush your plants with clean pH water, a couple times to ensure the root system was thoroughly cleaned.
Step 2: Try using balanced nutrients.
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Step 3: Dial down your nutrients.
Calcium Deficiency
Potassium Deficiency
Common Diseases and Treatment
A healthy plant is the best defense. --Maxim of the Garden Sage
As with most cannabis diseases, prevention is the best cure. Good hygiene and a clean grow area are the best ways to ensure your cannabis plants stay pest and disease free. Make sure you wash your hands before you enter your grow room and remove any discarded foliage or clippings.
Fungi thrive in warm and moist conditions and are an inviting food source for cannabis pests. Good air circulation and ventilation help keep the conditions at an optimum.
Gray Mold (Botrytis)
Of the diseases or fungi that attack cannabis plants, Gray mold or Botrytis is the most common for indoor grows. It thrives in humid conditions, mostly infecting plants which are around two weeks from harvest.
Treatment: Use sterilized scissors to remove infected buds at least an inch below the infected area, making sure you take it out of your grow room and destroy it. Wash your hands and sterilize your scissor thoroughly afterwards. The best cure is prevention; keep the humidity of your room to around 50% during flowering and make sure your grow room is clear of any discarded foliage.
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Damping Off
Damping off is a term used for the sudden death on new plant seedlings. It can be caused by any of a handful of fungal diseases, including several root rots (Pythium, Phytophthora) and molds (Sclerotinia or white mold, Botrytis or gray mold).
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Treatment: There is no cure for damping off. Prevention is key to avoiding damping off. Have accurate airflow and controlled humidity in your nursery.
Green Algae
Algae is slimy in its appearance, thrives on light, and is usually found on the surface of your growing medium.
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Treatment: You can treat it with Algaecide, which can be added to your nutrient solution or water.
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Downy Mildew
Downy mildew is sometimes called false mildew and affects vegetative as well as flowering cannabis plants.
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Treatment: Remove the plant and destroy it. Removing the foliage is not enough and will cause subsequent grows to become infected.
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Powdery Mildew
Occurs when temperatures are below 76° F (26° C) and it appears as a whitish-yellow spot on top of leaves, creating pale patches on leaves.
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Treatment: Remove the infected plant if it was isolated from the grow-room/ other plants. If it has spread amongst the room, a fungicide is required. Make sure to read the manufacturer's instructions for proper dosing.
Root Rot
Root rot is caused by a lack of oxygen being supplied to the roots either by overwatering or supplying them with un-aerated water.
Treatment: As well as keeping your medium clean, take measures to avoid over-watering your plant or using a medium that has poor water drainage
Common Pests and Treatment
Pests are organisms which damage or interfere with desirable plants in our fields, orchards, landscapes, or wildlands, or damage homes or other structures. Pests also include organisms which impact human or animal health. Pests may transmit disease or may be just a nuisance. A pest can be a plant (weed), vertebrates (birds, rodents, or other mammal), invertebrate (insect, tick, mite, or snail), nematode, pathogen (bacteria, virus, or fungus) which causes disease, or other unwanted organisms that may harm water quality, animal life, or other parts of the ecosystem.
Spider Mites
Spider mites are the most common cannabis pests found in indoor cannabis growing. Left untreated, they will slowly drain the life out of your plant(s). They will be found on the undersides of leaves; they enjoy hot and dry climates. High reproduction rates occur in ideal environments with a temperature of 85-90°F (29-32°C) with humidity at 50% or lower.
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Treatment: You can combat spider mites by spraying plants with neem oil or pyrethrum. An alternative measure is to introduce ladybugs to your grow room as ladybugs will eat spider mites.
Prevent an infestation by keeping your grow room clean and make sure all tools are cleaned and sterilized regularly.
Fungus Gnats
Fungus gnat larvae attack seedlings, roots, or weak plants, causing plants to lose vigor thereby making them open to other cannabis diseases. As fungus gnats are commonly found in dark and damp conditions, they thrive in NFT hydroponics setups.
Treatment: Treating gnats can be a challenging process as a multi-stage attack is required for elimination to be complete. Mist kits and sticky strips are great for catching adult gnats. The most effective control for larvae is steinernema feltiae (a predatory nematodes).
Thrips
Adult thrips are small, fast-moving insects, while young thrips look like tiny unmoving pale worms on the leaves. In fact, thrips can come in many forms, from wormy nymphs to dark or golden winged insects, depending on the stage of life and where you live. They pierce cannabis leaves with their mouths and suck out all the chlorophyll.
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Treatment: Thrips have been a long-term greenhouse pest and over the years have developed a tolerance to most insecticides. If biological controls (beneficial insects-predatory wasps or cucumeris) are not used during vegetative stage, later infestation can be extremely hard to get under control. Thrips exchange bodily fluids with the plants as they feed the chances of a viral infection is likely.
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If predatory insects are not an option, treatment consisting of pyrethrin products and biological insecticides which contain bacillus thuringiensis that kills thrips when it is consumed.
Aphids
Aphids are soft-bodied insects which can appear white, green, yellow, black, brown, and red, depending on their stage of life and where you live. Thankfully, these insects are very rare when it comes to indoor gardens. They are small, round and usually light green, although there are hundreds are variations. Aphids produce large amounts of a sweet substance known as “honeydew,” a sugary liquid waste. Honeydew drops from these insects can attract a type of fungus called sooty mold which can grow on honeydew deposits accumulating on the leaves and branches of your plant, turning them black. The drops of sweet honeydew can also attract other insects such as ants.
Treatment: Ladybugs are often used as a predator and are amazingly effective if released in large numbers. Insecticidal soaps, and neem oil are great for treatment as well.
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Other pests typically attacking cannabis plants are: Mealybug, whiteflies, leaf-miners, and scales. These soft-bodied insects can be successfully treated with an array of insecticides or beneficial insects. Many cannabis growers find insecticidal soap to be a good cure for these less intrusive soft-bodied bugs.
Outdoor Pest Management
Integrated Pest Management (IPM) is an ecosystem-based strategy focusing on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.
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IPM programs normally implement a combination of treatments or control practices which prevent or treat a problem from many different angles. The control practices used in an IPM program can be categorized as biological, physical, cultural, or chemical.
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Biological: using beneficial plants, insects, or microorganisms to control pest/insects and damage they cause. Most pest/insects have a natural predator. Ladybugs and beneficial nematodes are just two examples of biological controls.
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Physical: this is a control which kills pest/insects directly or physically stops them from entering the garden space. Sticky traps to catch flying pest/insects and barriers to keep rodents or deer out of the garden are examples of physical controls.
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Cultural: these are practices which reduce the pest/insect’s ability to establish itself. For example, a change in irrigation practices can reduce moisture at certain times throughout the day, making it difficult for particular pests to thrive.
Chemical: Chemical control is the use of pesticides. For most IPM programs, chemical control is only used when needed and is used in conjunction with other techniques to maximize effectiveness and to create long-term solutions.
PPM/EC and pH
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EC Meters (electric conductivity)
Usually found in hydroponics, aquaponics, aeroponics and freshwater systems - read the electric conductivity in the nutrient solution. This is important in detecting the health of your plants. High saline content could lead to toxicity or nutrient lock out in the plant. Too low of a saline reading could indicate there is a nutrient deficiency.
TDS(PPM) Meter
Total dissolved salts or parts per million (PPM) meters are used to detect the exact concentration of solubles (minerals) in the nutrient solution and/or reservoir. 1 part per million is the equivalent of 1mg of solubles per liter of water which is a miniscule amount to measure. Most tap water has minerals in the range of 150-400 ppm. TDS meters can vary in price and reading capacity; for cultivation meters, most will not read past 3500 ppm. Maintenance or calibration of these meters are critical for their success in future readings.
When it comes to growing cannabis, there is not much of a difference between EC and TDS Meters. Many TDS meters measure the electrical conductivity of liquids, and then convert those results into ppm. In other words, many TDS meters are EC meters in disguise!
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pH
pH ranges from 0-14; 0-6 being acidic, 7 being neutral and 8-14 being alkaline. Cannabis likes a slightly acidic environment at the roots. Proper pH at the roots helps plants get access to nutrients. If the pH at the roots is too high or low, the plant cannot properly absorb nutrients; nutrient deficiencies or toxicity may occur. Nutrients take different forms (on a chemical level) depending on the pH around them. The way liquid nutrients are formulated, they are highly available to plant roots, but only in the right pH range. If you stick within the recommended pH ranges below, you will prevent most of all nutrient problems caused by too-high or too-low pH.
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Soil: 6.0-7.0 pH
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Hydro/soilless/coco-coir: 5.5-6.5 pH
Hydro and Soil pH Chart:
Indoor Grow Checklist:
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Where are you going to grow? You need to create a light-tight growing environment with ventilation, a good breeze, and enough room to hang your grow lights above your plants. Many indoor growers build custom grow spaces or invest in a pre-made grow tent.
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What grow lights are you going to use? Since you do not have access to the sun, you must provide all the light your plants need. NOTE: it is almost impossible to grow a cannabis plant in a window.
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What growing medium do you plan on using? Soil or hydro? You want to find a grow method that best fits your schedule and style.
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Easy access to water? You do not want it to be inconvenient to water your garden.
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Will you grow with nutrients? Most growers add some sort of nutrients or supplements. In hydro, you must provide all nutrients since there are not enough nutrients in plain water to feed your plants. Whether you are growing in soil or hydro, you can buy pre-formulated cannabis nutrients or mix your own custom blend.
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Temperature of your grow area? Cannabis plants enjoy a comfortable room temperature. Many grow lights can produce a lot of heat, which means you may need to consider ventilation and an exhaust system to maintain a constant and consistent temperature. Cold is less often a problem indoors but remember very cold and freezing temperatures will kill cannabis plants.
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What about smells? If you have invested in an exhaust system, you will likely want to invest in an exhaust fan with a carbon scrubber to automatically neutralize all smells in your grow area. You may also want to consider growing a low-smell strain. (checklist borrowed from Grow Weed Easy - https://www.growweedeasy.com/marijuana-indoors-vs-outdoors-checklist )
Growing Outdoors
Climate Considerations: Excessive heat over 86°F (30°C) will cause the plant to stop growing. Temperatures under 55°F (13°C) will cause damage and stunting to the plants, even death in extreme cases. Heavy winds, hail, and rains will sustain damage to the plant, as well as excessive moisture can lead to molds or mildews. Understanding the light period in your area is crucial for knowing when your plant will flip into flowering, giving you an idea when to prepare for harvest. Some areas get 14-18 hours of light, while others only get 10 hours of light.
Location Concerns: Your cannabis plants should receive as much direct sunlight as possible, ideally during midday, when the quality of light is best. As the season changes and Autumn approaches, your plants will get less and less sunlight throughout the day, which will trigger the flowering stage. Having a consistent breeze is good for your plants, and especially in hot climates. With Canada’s Cannabis legal framework, by law to grow your 4 legal plants outside you must have them securely hidden behind a 3.52m (11.5 foot) fence.
Mediums: Growing cannabis in pots outdoors allows for easy moving in the event a quick relocation is required (e.g. frost, damaging storm). Although you can grow in a flower bed or designed area in the ground, be aware your plants are stationary; you will need to bring protection to them.
Genetics: The main drawback to growing from seed – unless you specifically buy feminized seeds, you could end up with both males and females, in which case you’ll need to sex them out to get rid of the males (only females produce buds). A lot of beginning growers start with feminized seeds. Even when you do have all female plants, each will be a different phenotype of the same strain. To get the best version of that strain, you will need to select the best phenotype, which can be a lengthy process.
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Plant protection: Having a greenhouse or an area you can relocate your plants temporarily is something to consider. Cannabis can handle fluctuating temperatures and humidity. However, too hot can cause damage to growth and cause the plant to stop its growing process altogether. Too cold can damage the roots, new growth and cause internal shock to the plant - possibly stunting its growth.
Wind Conditions and Rain: High winds can break branches and stress your plants. If your garden is in a windy spot or if you are expecting a particularly strong windstorm, set up a windbreak. This can be as simple as attaching plastic sheeting to garden stakes around your plants.
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While helpful for watering your garden, rain is generally seen as a nuisance by cannabis growers. It can severely damage your crop and cause mold and mildew. You do not want to rain on your cannabis plants when they are flowering. You can construct a DIY greenhouse or even just use plastic sheeting and stakes to build a temporary shelter over your plants when you know rain is on the way.
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Pests: Protecting your cannabis garden from pests can be challenging. The most difficult challenge is dealing with the vast array of crawling and flying insects which may attack your plants. Besides the suggestions listed previously under “Integrated Pest Management”, the best protection is to simply keep your plants healthy. Strong, vigorous cannabis plants have a natural resistance to pests which helps them fight off minor infestations. It is also a good idea to keep your cannabis plants separate from other flowers, vegetables, and ornamentals, as pests can easily spread between them.
Germination Steps
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Germination: Germination happens when the outer shell of the cannabis seed cracks open and the small taproot protrudes. Appearance of the taproot means germination was successful.
Cannabis Seeds need 3 factors for them to germinate successfully:
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√ Moisture √ Warmth √ Darkness
Germination: Cup of Water to Paper Towel (steps provided by Crop King Seeds)
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Step One: NOTE: Use spring water or Reverse Osmosis water ONLY
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Before germination, start by preparing your workspace. Ensure everything is cleaned to prevent cross contamination, and make sure you have all the necessary materials. You will need:
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absorbent kitchen paper towels (not facial tissue),
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distilled water / bottled spring water without additives or gas (NOTE: boiling water only kills germs, it does not remove impurities),
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a glass,
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a plate, and
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tweezers.
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Fill the glass with water and leave to stagnate in a room with a temperature of between 20 to 25 degrees Celsius (a little higher than room temperature).
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Drop the seeds into the room-temperature water and you will see them float. Leave them to soak for 12 – 18 hours. Soaking the seeds is the most important step.
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Check the seeds after you have let them soak for a few hours. Tap them with your fingertip gently. You may see them sink to the bottom.
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You might notice the seed shell crack and a small white root appearing. This indicates germination is beginning. It is okay if the shell has not cracked by the end of the 14-18-hour water soak.
DO NOT ALLOW YOUR SEEDS TO SIT IN THE CUP OF WATER MORE THAN 18 HOURS
Warning: Tap roots should be left to grow to a length of 3cm or 1 inch.
Step Two: How to prepare your paper towel method set up
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After you have noticed the seeds cracking open and a small white root forming, take two or more paper towels to create a thick, folded layer on the plate. Moisten with distilled water (or rainwater). Wet the paper towels just enough to be damp, but do not over-saturate. Drain any excess water.
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After 14 – 18 hours of soaking, add the cannabis seeds in between the 2 folded wet paper towels. Allow the seeds enough space apart from each other to prevent new taproots from tangling.
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Leave the germination plate in a closed dark space and do not forget to keep the layers moist by dripping some water every 5-12 hours. No need to soak them, just keep them wet.
NOTE: Never let the paper towels dry out. The paper towel must stay moist. Depending on humidity, the towel may need re-moistening every 5 hours (your experience may vary). It is necessary to regularly check on the dampness of the paper towels during the process.
Step Three
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Place your plates with completed germination set up away from direct light, on a warm appliance/heat source to help the seeds absorb more water. Keep the room temperature at 21 to 29.4 degrees Celsius.
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Note: Providing the seeds with moisture, warmth, and darkness encourages better results
Step Four
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Check the cannabis seeds and paper towels at least two or three times every 24 hours, but do not touch the seeds. Make sure there is a proper level of moisture in the paper towels and watch for new taproots to appear.
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If you must handle cannabis seeds, gently use tweezers. Be very careful in moving them because seeds during this stage are so fragile, they can easily be damaged when being transported or transplanted. Do not touch the taproots.
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When the new taproot is about ¼ inch to ½ inch long, the germination process is complete. At this point the cannabis seeds are ready for placement into soil; taproot facing down.
IMPORTANT NOTES:
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Most seeds will start germination within 24 to 48 hours, but some can take as long as seven days. (depending on the cannabis strain). Please follow the directions outlined above, and you will experience minimum 80% germination success. The paper towel method is designed to replicate the process most closely as it occurs naturally by Mother Nature.
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Germinating any seed may fail depending on the following variables:
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You have not allowed the seeds to sit in the cup of water long enough
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Paper towels are too wet or too dry
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Temperature is too hot
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Temperature is too cold
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Do not suffocate them in plastic; seeds need to breathe
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Tap water has many impurities
Vegetative Stage
Plants will start their life in the nursery, and then as they mature, they will be moved to a vegetative grow room. In this room, plants will increase in size as they put most of their energy into stem growth and leaf development.
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However, once the plants begin to switch to flower production, they need different light levels, temperature control, and other special considerations. Moving pre-flowering plants to a flowering grow room allows the grower significant control during this important stage.
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As a rule, MORE LIGHT = FASTER GROWTH
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During the vegetative stage, cannabis plants which do not get enough light will tend to “stretch” up toward the light with a lot of space between nodes (branches). This is not usually a good thing, because tall lanky plants are hard to give proper light coverage.
During the flowering stage, light intensity is what drives the production of buds (flowers). For the best results, you want all your buds directly exposed to strong light. Even if you run into major problems in the vegetative stage, you can bring your plant back from the brink of death simply by addressing the problem and giving your plant some T.L.C. Ideally you want to give your plant a rest period for cellular development. Generally, 18 hours light and six hours of darkness is a rule of thumb for vegetative lighting.
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Choosing the right size pot for your plants is essential. Smaller pots create smaller plants. Generally, you only want to transplant 2 times in a cannabis plants life cycle.
General rule is 18” tall plants can be switched into flowering, ideally this can be anywhere from 5-8 weeks of vegetative growth. Be aware your plant with double if not triple in size once flipped into flowering. Judging your room size, and light efficiency will help you decide at what height to flip them into flowering.
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Topping Off
Topping a plant refers to cutting off the top shoot(s) of cannabis plants.
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You can pinch, clip or snip off the tallest shoots, ideally the 4th internodes new growth. Cut the new growth where the two branches connect to the stalk. The plant will start developing branches at the remaining nodes.
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This is a good technique to keep a plant short and bushy. Ideally working with 3-4 main colas will give you the best chances for more mass in bud development.
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Top ten tips for successful vegging:
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Compost teas or Premixed Nutrients: Pre-select your nutrients or have your compost tea made and ready for use by the time the vegetative state comes.
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Fabric versus Plastic: Choosing the right pot will help benefit plant root development. Fabric pots offer your plant 100% aeration to the roots, where plastic pots limit oxygen intake. The prices vary substantially between fabric and plastic, plastic being the economic version for pot selection.
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Air Pockets: perlite and vermiculite are excellent choices when it comes to creating air pockets in your pots. Using a mix or 25-50% perlite (or vermiculite) will not only improve the wicking action of the root zone but it will also allow the flow of oxygen and nutrients to never be compromised.
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Encouraging the Roots: Roots grow in various directions in search for moisture. By mastering the balance between wet and dry will encourage young plants to work hard on root development.
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Foliar feeding: Although the roots are working hard, additional nutrients to plant leaves increase plant growth and structure. A homemade mild mix of Humic acid, molasses or seaweed extract is best used for a foliar feed. Lightly mist the tops and bottoms of the leaves during morning or evening of your plants light cycle. Avoid foliar feedings during the hottest time of the day.
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Training: Incorporating low-stress techniques (L.S.T) and high-stress techniques (H.S.T) will not only improve vigor, plant health, structure, and auxin production, but it will also significantly improve your plants yield.
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Beneficial Bacteria and Fungi: The magic underneath the soil is all thanks to the advanced network of mycelium. Mycelium will improve the uptake of micro and macronutrients to your plant.
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Support: You can still do plant training while you are supporting your plants. Especially outdoors – you want to make sure your plant is strong enough to withstand gusts of wind.
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Seaweed Based Products: Seaweed contains natural growth hormones ranging from auxins, indoles, and cytokinins, as well as micronutrients.
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Humidity and Temperature: To keep the plants performing at peak optimal conditions, indoor gardeners should aim for a daytime temperature of 24°C/75°F, with a relative humidity of 65-75%.
Flowering Stage
In many indoor gardening setups, separate areas are used to hold plants in different stages of growth. This allows the grower to control the amount of light, humidity, water, and temperature to ensure optimal growth and development at each stage. There are many factors which trigger a plant to start flowering. The need for external stimulation is usually required to bring on the morphological changes.
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Light: Ideally flowering rooms light cycles are 12 hours on and 12 hours off (autoflowers can be adjusted to this light cycle or left on the light cycle they started vegetative growth with). Both the number of hours of light and the wavelengths influence the onset of flower development.
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NOTE: Disrupting the dark period can have catastrophic effects on the yield, sending the plant into a confused state, sometimes resulting in a hermaphrodite plant, or buds full of seeds.
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Fertilization: Another factor to induce flowering is switching your nutrients from a grow formula to a bloom/ flowering formula. During the vegetative state, the plant requires higher levels of nitrogen and sulfur to help build amino acids, the building blocks of life. Once the plants switched into flowering the plants demand for potassium increases while its demand for nitrogen decreases. Phosphorus requirements also increase to help drive ATP metabolism (energy sources that transport things in and out of the cell).
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CO2: During flowering, the need for CO2 increases. With supplementation of CO2 you will help stimulate the plant into flowering, increasing yields, prevent flower loss, reducing stress, ripening of the flowers and reduce flowering times.
NOTE: Scrogging a plant. As pictured, scrogging involves an adjustable net at the top of the plant where any flowers at the top of the plant will be placed through the net. You then can move the net up as the plant grows.
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Scrogging your indoor plants will only benefit and give equal parts of light to each bud. Scrogging nets also help as support for later flowering bud weight issues.
Cannabis Flowering Stage Timeline
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Week 1–2 Transition to flowering: Your plant will double, sometimes triple in size. White pistils will begin to show (PPM no higher than 1100).
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Week 2–4 Flower buds form: Bud sites are now developing and noticeable. The plant has begun transitioning growing structure to only bud formation.
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Week 4–6 Buds start producing weight: Trichomes have been developed at this point, fan leaves may start to yellow. Nutrient level ideally around 900ppm.
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Week 6–8 Buds ripen, pistils darken: check trichomes, if beginning to ripen begin your flush-ideally this last 2 weeks. Leaves will be yellow and falling off. NOTE: some strains spend longer in this stage
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Week 8 and on Flowering ends, final flush: final runoff should read 100ppm or less.
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Final Stages
Flushing
This is the final step before harvesting! Many growers do a final flush, which involves giving only plain water to your plants (up to a few weeks) before harvest. There are flushing products on the market that help the grower remove the unneeded nutrients/salts your plant has not used. You are basically just maintaining your plant until harvest. Keep a close eye on the buds, pistils and trichomes to help you figure out the best time to harvest to achieve to get the desired results. PPM meters can get you exact nutrient levels for a more accurate reading on when to begin harvesting. At this point it is completely normal for your plant leaves to start yellowing, sometimes rapidly.
Harvesting
Your hard work has almost paid off. Harvesting can be done by a trim machine or by hand. Higher quality buds come from hand trim work but take more time to complete the task. Where a trim machine may not be as detailed but will cut your harvest time in half, sometimes even 75%! Trim machines can be fairly pricey, in the $1000 and up range. Choose which method would be beneficial for your operation. One more major step after the pleasure of harvest day: curing your plant
Curing
Here is what drying and curing cannabis properly does for the completed flower/buds:
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Breaks down chlorophyll; improves taste and smoothness of buds;
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Brings out the subtle flavors and unique smell of your cannabis strain;
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Reduces the chance of mold or bacteria growing on your buds; and
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Curing increases potency.
Optimal Drying Environment:
Room Temperature – Around 70°F (21°C)
50% Humidity
Optimal Environment in Jars (Curing):
Room Temperature – Around 70°F (21°C)
58-65% Humidity
Curing can involve different processes for different types of plants. For instance, some plants require a two-step process that involves drying, and then curing. Medicinal herbs are usually placed in glass jars for several weeks once they have been dried in order to enhance the flavor and potency of the product.
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Some plants can also be sun-cured, which entails hanging the plants in the full sun to dry. Heat can also be used to cure plants. The leaves are hung on sticks and exposed to low heat. Great care is taken not to have smoke or fire near the leaves during the curing process.
Some types of tea leaves must be exposed to heat during curing so that they oxidize and become sweet. Plants can also be placed in a brown paper bags or mason jar in a warm, dry location to successfully cure. Curing time varies depending on humidity, the type of plant involved, and the
water content of the plant at the time it is harvested. There are a few different methods of drying and curing plants, but it all cases, environmental control and the duration of the drying period are what ultimately lead to a quality product. Throughout the curing stage, products must be closely watched to ensure mold growth doesn't occur.
www.maximumyield.com (What is Curing?, 2019<www.maximumyield.com>)
Disinfection, Sanitizing, and Sterilization
What is the difference between disinfection, sanitization, and sterilization?
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Disinfection is the process of cleaning something, especially with a chemical, to destroy bacteria.
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Sanitization refers to a thorough cleaning.
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Sterilization takes things a step further, focusing on the complete eradication of microbes.
Many pathogens can be managed to some degree using disinfectants. For example, dust particles from fallen growing medium or pots can contain bacteria or fungi such as Rhizoctonia or Pythium. Disinfectants will help control these pathogens. As well, some disinfectants are also labeled for managing algae which is a breeding ground for fungus gnats and shore flies.
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When it comes to indoor grow operations, daily sanitization is extremely. Any spills, excess water, filth, and debris all pose risks to the health and well-being of both humans and plants.
Sterilization goes beyond simple cleaning. It eliminates things like mold spores, fungi, viruses, and bacteria. Many methods exist for surface sterilization, including heat and chemical cleaning solutions (usually bleach and hydrogen peroxide).
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Common products used are Isopropyl 99%, hydrogen peroxide, and any natural all-purpose cleaners. For all growers, cleanliness is a top priority to establishing a containment free indoor grow room.
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Tips and Tricks for Maximizing Yield
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Be patient
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Research, ask opinions, but don’t get lost in a sea of options. Plan out a general grow path and schedule, tweak as needed.
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Pay attention - your plants will talk to you about how they are feeling; there are early warning signs of potential issues.
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Do not over nutrient your plants; force feeding is not good
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Genetics also play a part – research the best strain you are looking to grow.
Glossary
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Aeroponics: a plant-cultivation technique in which the roots hang suspended in the air while nutrient solution is delivered to them in the form of a fine mist.
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Aquaponics: a system of aquaculture in which the waste produced by farmed fish or other aquatic animals supplies nutrients for plants grown hydroponically, which in turn purify the water.
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Compost Tea: Compost tea is a concentrated organic liquid fertilizer made from steeping biologically active compost in aerated water. Compost tea is nutritionally rich and can help provide plants with beneficial soil bacteria. A compost tea is generally produced by combining one volume of compost material with several volumes of water.
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Flowering: the flowering stage refers to the phase where plants produce their flower sets, vegetables, and fruits.
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Feminized: Feminized plants come from seeds that have been selectively bred to produce only female plants.
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Hydroponics: Hydroponics refers to a system of gardening that does not use soil. Plants are grown in water and receive their nutrients from the addition of solutions rather than soil.