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Cannabis Growth Cycle – Step by Step

Written by @redlegcultivator

In this cannabis growth cycle article, I will lay out and discuss the standard operating procedure I developed for a legal commercial grow in a legal medicinal cannabis state in the United States. Please keep in mind that this is not meant to be the only way. This plan was developed over years of continuous research and testing and ultimately is what worked best for me. I am putting this information out to give a basis for one to follow while continuing to develop their own version of a final product. There are times when I have to deviate from this plan based on any number of factors, most of all plant health and performance. Given that, this plan will serve as the backbone of all plans going forward,no matter the size of the canopy.  

This commercial grow was designed to have thousands of plants in flower at any given time. The vegetative room was designed with a multi-tiered area with sets of clone moms and multiple clone racks. Each flower room, of which there were fourteen, had approximately fourteen hundred square feet of plant canopy. Plants in this instance would have been trained out under netting to approximately eight to nine square feet of canopy each.

Fret not home grower. This plan also works with any number of plants you can grow legally. One can start a run from seed to finish in a tent with this plan. I use this plan at home for my medical patient personal grow.  This plan is to be used with any hydroponic media and nutrients. I have listed some products I use in this plan. Feel free to substitute or remove anything to make it easier for your own situation or experience.

In the end, growing is all about attaining results. Get the results you want from whatever method you use. This is what I use. Enjoy.

Redleg Cultivator

“SAPERE AUDE!”

P.S. I will explain my complete nutrients line-up in a following article.

Cannabis Growth Cycle Standard Operating Procedure Sample

Seedling Germination

Light Cycle24-18 HRS, 40-60 µmol, 24”-36” above canopy
Light SpectrumVegetative Lighting 6500 Kelvin
Temperature78-82 Degrees Fahrenheit
Relative Humidity75%-85%
Length7-9 Days

Nutrient Solution: Reverse osmosis water, 1mL/gallon Dutch Pro Take Root®, 5ml/gallon Clonex Solution®. Mix parts separately into the final volume of water and mix well. Adjust pH to 5.5 after all parts are mixed.

Process: Soak pre-sanitized cube media in pH corrected 5.5 solution. Place the cube media in the seedling trays and domes. Allow the cube to drip dry, so that it is not soaked, but moist. Place the seed, tip down, in the hole of the cube media. Push down until the tip of the seed makes contact with the bottom of the cube hole. In 2-5 days, all seeds should be sprouted with leaves and taproot out of the cubes. Discard those that are not.

Once most of the seedlings have sprouted, add 400mL of pH corrected solution to the clone trays. Do not soak the media. We want the roots to chase the water in the tray, and they will not do so as fast if you soak the media. Replace the water every two to five days or as needed until transplant.

Once the seedlings have germinated, open the vents on the dome, then slide the dome to the side to allow for more airflow.  

Cloning Propagation

Light Cycle24-18 HRS, 80-200 µmol, 24”-36” above canopy
Light SpectrumVegetative Lighting 6500 Kelvin
Temperature78-82 Degrees Fahrenheit
Relative Humidity70%-80%
Length7-14 Days

Nutrient Solution: Solution of reverse osmosis water, 1mL/L Dutch Pro Take Root®, 5ml/L Clonex Solution®. Mix parts separately into the water and mix well. Adjust pH to 5.5 after all parts are mixed—10 to 20 mL of Clonex Rooting Gel® in a small cup.

Process: Soak pre-sanitized cube media in pH corrected 5.5 solution. Place the cube media in the seedling trays and domes. Allow the cube to drip dry, so that it is not soaked.

Starting at the bottom of the mother plant, take 3 to 4-inch cuttings with at least three nodes. Cut the bottom of the stem at a 45-degree angle. Clip the tips of all leaves off—place cuttings into a cup with nutrient solution. Score the bottom inch of the clone stems to increase surface area, but do not cut so deep that the stem is cut through. Dip the cloned stem into Clonex Rooting Gel® and wipe off most of the excess. Place the cloned stem into the cube media hole and push into the cube half to two-thirds of the way in.

Place 400mL of nutrient solution in the bottom of the clone tray. Place clone cube tray with clones into clone tray and cover with the dome, vents closed.  

Do not open the dome, if possible, for the first 36 hours. Days 4 through 9, slide open the dome and open the air vents for 1 to 2 hours per day for airflow, then close all vents and slide domes back on the tray. On days 9 through 12, there should be roots showing through the cubes, and the domes should be slid open and the air vents completely open at all times. Domes should be left completely off for days 12 through 15 until transplant.

Add or change nutrient solution every 2-5 days or as needed into the bottom of the clone try. Do not soak cubes. Apply directly to the tray bottom.   

Cannabis Growth Cycle

Early Vegetative Stage Week 1

Light Cycle18 HRS, 400-600 µmol, 36” above canopy
Light SpectrumVegetative Lighting 6500 Kelvin to 3100 Kelvin
TemperatureLights on 82-86 degrees Fahrenheit/ Lights off 77-82 Degrees Fahrenheit
Relative Humidity60% to 65%
Length7 days

Nutrient Solution: Preferred hydroponic nutrient line, reverse osmosis water 60 to 70 degrees F, pH adjusted to 5.5-6.5  

Feeding Style: Vegetative

Process: Soak pre-sanitized hydroponic grow media in week 1 nutrient solution until runoff, which should be approx. 65% media moisture content. Transplant clones into pre-soaked grow media, completely covering roots. Set drippers into media on either side of clone.

After the transplant, wait for media to dry back initially to 35%-45% moisture content (3-7 days). Begin first feedings after this dry back is achieved.

Feedings should be 10%-15% of pots volume, ultimately bringing the moisture content up to 50% to 55% total moisture content before coming to runoff at last feeding. Feedings should start 1-2 hours after lights on and stop prior to 2 hours before lights off.   

Cannabis Growth Cycle

Overnight media dry backs should be 10%-15% moisture content.

With proper overnight dry back, there will be 8 feedings during lights on. Beginning at hour 2 of lights on, 2% of pots volume will be applied every two hours ending with the hour 16 of lights on application. Runoff should not be achieved until last feeding of the day.

The average moisture content of media should be 50%-55% Lights on/ 35%-45% lights off.

Mid to Late Vegetative Stage Week 2-4

Light Cycle18 HRS, 400-600 µmol, 36” above canopy
Light SpectrumVegetative Lighting 6500 Kelvin to 3100 Kelvin
TemperatureLights on 82-86 degrees Fahrenheit/ Lights off 77-82 Degrees Fahrenheit
Relative Humidity55%-65%
Length7-28 days

C02 PPM: Lights on CO2 system on 700-1000 PPM/ Lights off CO2 system off, ambient PPM approx. 400 PPM

Nutrient Solution: Preferred hydroponic nutrient line, reverse osmosis water 60 to 70 degrees F, pH adjusted to 5.5-6.5 

Feeding style: Vegetative

Process: Topping, pinching top nodes, super cropping and low stress training start in late-week one and week two. This is done to maintain proper canopy height, density, and uniformity. Undercutting will be done in week 2 in preparation for flip to flower.

Feedings should be frequent and light volume. Daily feedings should be 10%-15% of pots volume, ultimately bringing the moisture content up to 50% to 55% total moisture content before coming to runoff at last feeding. Feedings should start 1-2 hours after lights on and stop prior to 2 hours before lights off.  

Overnight media dry backs should be 10%-15% moisture content.

With proper overnight dry back, there will be 8 feedings during lights on. Beginning at hour 2 of lights on, 2% of pots volume will be applied every two hours ending with the hour 16 of lights on application. Runoff should not be achieved until last feeding of the day.

The average moisture content of media should be 50%-55% Lights on/ 35%-45% lights off.

Transition to Bloom/ Through Day 21

Light Cycle12 HRS, 600-800 µmol, 36” above canopy
Light SpectrumBloom Lighting 4000 Kelvin to 2100 Kelvin
TemperatureLights on 82-86 degrees Fahrenheit/ Lights off 76-80 Degrees Fahrenheit
Relative Humidity55% to 60%
Length 21 days
.;

Nutrient Solution: Preferred hydroponic nutrient line, reverse osmosis water 60 to 70 degrees F, pH adjusted to 5.5-6.5 

Feeding style: Generative

Process: Switch nutrients solution to bloom. Change to Generative feeding style—switch lighting to 12/12 (actual times will be 11:30 on and 12:30 off). The day before flip, undercut plants so that only the top four to six nodes are left on the branches. Maintain even canopy height by bending branches under the netting and super cropping/LST.

Generative style feedings should be 4% to 6% of the media volume until runoff is achieved between hours 5-6 of lights on. Target is 15% to 25% of media volume, and given proper overnight dry back, should bring the medium’s,moisture content to 50% to 60%.

Additional feedings between hours 6 and 10 of lights on, consisting of 2% to 3% media volume to maintain moisture levels until lights off.

Feedings start 2 hours after lights on, ending 2 hours before lights off.

Overnight dry backs should be 15% to 25% of media volume. Lights on average moisture content will average 50% to 60%. Nighttime moisture content should be an average between 35% and 40%

Cannabis Growth Cycle

With proper overnight dry back given approximately 40% moisture content, there will be three feedings of 6% media volume at hours 2, 4, 6 of lights on bringing approximate moisture content to 58%. Additional feedings of 3% at hours 8 and 10 of lights on will maintain medium moisture at approximately 58% to 60% until lights off/ dry back period.

Mid Bloom Days 22 through 42

Defoliation on day 22 will strip all of the large fan leaves on each branch from the bottom up, leaving the 4 largest at the tops. This allows light to reach lower bud sites. Bud sites below the secondary net should be removed. Irrigation will drop 30% to 50% volume for several days as the plants will not transpire as much with less leaf surface.

Light Cycle12 HRS, 800 µmol, 36” above canopy
Light SpectrumBloom Lighting 4000 Kelvin 2100 Kelvin
TemperatureLights on 80-82 degrees Fahrenheit/ Lights off 74-76 Degrees Fahrenheit
Relative Humidity50% to 60%
Length 21 days

C02 PPM: Lights on CO2 system on 1400-1600 PPM/ Lights off CO2 system off, ambient PPM approx. 400 PPM

Nutrient Solution: Preferred hydroponic nutrient line, reverse osmosis water 60 to 70 degrees F, pH adjusted to 5.5-6.5  

Feeding style: Vegetative

Vegetative style feedings should be 1% to 3% of the media volume until runoff is achieved between hours 5-6 of lights on. Target is 10% to 15% of media volume, and given proper overnight dry back, should maintain the medium’s moisture content at 50% to 60% while lights are on.

Cannabis Growth Cycle

Feedings start 2 hours after lights on, ending 2 hours before lights off.

Overnight dry backs should be 10% to 15% of media volume. Lights on average moisture content will average 50% to 60%. Nighttime moisture content should be an average between 40% and 45%

With proper overnight dry back given approximately 45% moisture content, there will be five feedings of 3% media volume at hours 2, 4, 6, 8, and 10 of lights on bringing approximate moisture content to 60%.

Late Bloom Days 43 through 64

Light Cycle12 HRS, 800 + µmol, 36” above canopy
Light SpectrumBloom Lighting 4000 Kelvin to 2100 Kelvin
TemperatureLights on 78-80 degrees Fahrenheit/ Lights off 72-74 Degrees Fahrenheit
Relative Humidity50%-55%
Length 21 days approximately

C02 PPM: End Supplementation, ambient PPM approx. 400 PPM

Nutrient Solution: Preferred hydroponic nutrient line, reverse osmosis water 60 to 64 degrees F, pH adjusted to 5.5 

Feeding style: Generative

Generative style feedings should be 4% to 6% of the media volume until runoff is achieved between hours 4-8 of lights on. Target is 25% to 35% of media volume, and given proper overnight dry back, should maintain the medium’s moisture content at 50% to 60% while lights are on.

Feedings start 2 hours after lights on, ending when runoff is achieved.

Overnight dry backs should be 25% to 35% of media volume. Lights on average moisture content will average 50% to 60%. Nighttime moisture content should be an average between 25% and 30%

With proper overnight dry back given approximately 30% moisture content, there will be four feedings of 6% media volume at hours 2, 4, 6, 8, with lights on bringing approximate medium moisture content to 54%.

Flush Period

Light Cycle12 HRS, 800 + µmol, 36” above canopy
Light SpectrumBloom Lighting 4000 Kelvin to 2100 Kelvin
TemperatureLights on 75-79 degrees Fahrenheit/ Lights off 70-72 Degrees Fahrenheit
Relative Humidity50%-55%
Length 14 days approximately

C02 PPM: End Supplementation, ambient PPM approx. 400 PPM

Nutrient Solution: Preferred hydroponic nutrient line, reverse osmosis water 55 to 60 degrees F, pH adjusted to 5.5 

Feeding style: Generative

Generative style feedings should be 4% to 6% of the media volume until runoff is achieved between hours 4-8 of lights on. Target is 25% to 35% of media volume, and given proper overnight dry back, should maintain the medium’s moisture content at 50% to 60% while lights are on.

Feedings start 2 hours after lights on, ending when runoff is achieved.

Overnight dry backs should be 25% to 35% of media volume. Lights on average moisture content will average 50% to 60%. Nighttime moisture content should be an average between 25% and 30%

With proper overnight dry back given approximately 30% moisture content, there will be four feedings of 6% media volume at hours 2, 4, 6, 8, with lights on bringing approximate medium moisture content to 54%.

Cannabis Growth Cycle

Pre-Harvest

Light Cycle12 HRS, 600 + µmol, 36” above canopy
Light SpectrumBloom Lighting 4000 Kelvin to 2100 Kelvin
TemperatureLights on 60-65 degrees Fahrenheit/ Lights off 60-65 Degrees Fahrenheit
Relative Humidity45%-50%
Length3 days

C02 PPM: End Supplementation, ambient PPM approx. 400 PPM

Process: After completing the flush, do not feed the plant for 3 days—harvest when the medium moisture content is below the temporary wilt point of 30% moisture content.

Dry/Curing Period

Light CycleNo Lighting at all.
Light SpectrumN/A
Temperature55-65 degrees Fahrenheit
Relative Humidity55%-65%
Length10-14 days hang drying, then 7-14 days dry cure. After that, it’s placed in containers for burping.

Leave hanging until 80% of the branches snap when bent. Then place shucked buds in food-safe containers with no cramming for 3-7 days. Trim all remaining laves, then place back into the container for another 3-7 days. Then the product needs to be bagged and burped every day.

Cannabis Growth Cycle

 

    

Cultivation information, and media is given for those of our clients who live in countries where cannabis cultivation is decriminalised or legal, or to those that operate within a licensed model. We encourage all readers to be aware of their local laws and to ensure they do not break them.

Hattie Wells