I’d been hearing a lot about growing marijuana organically instead of using synthetic hydroponics nutrients and decided to give it a try. Now my marijuana plants are harvested, and here’s my organic marijuana grow report complete with feeding dosages, and a discussion of results.
Unless otherwise noted, all dosage measurements are in teaspoons per gallon.
Strains Grown: Blackberry Kush & Skywalker OG
Growing Media: Pro-Mix BX, with 10% added washed Perlite. I chose Pro-Mix BX because it has no added nutrients starter charge.
Base Nutrients/Grow Phase: Iguana Juice Grow/Mother Earth Super Tea Grow
Base Nutrients/Bloom Phase: Iguana Juice Bloom/Mother Earth Super Tea Bloom
Additives, Grow Phase: Voodoo Juice; Tarantula; Piranha; Ancient Earth; Organic B
Additives, Bloom Phase: Same additives as used in grow phase, but also Nirvana; SensiZym; Rhino Skin; Bud Candy.
Base Nutrients Grow Phase Feeding Measurements: 2.5 teaspoons per gallon Iguana Juice Grow used alone. 3.5 teaspoons Mother Earth Organic Super Tea used alone. When I used these two bases together, I combined 2 teaspoons of Iguana Juice Grow with 1.5-2 teaspoons Mother Earth Organic Super Tea Grow.
Base Nutrients Bloom Phase Feeding Measurements: 3.5 teaspoons per gallon Iguana Bloom used alone. Four (4) teaspoons Mother Earth Organic Bloom used alone. In combination, 2 teaspoons Iguana Bloom and 2.5 teaspoons Mother Earth Bloom.
Grow Phase additives measurements: Started listed additives (above) at week two of grow phase, following manufacturers recommended dosages.
Bloom Phase additives measurements: 1.5 teaspoon per gallon Rhino Skin every other feeding. 2 teaspoons Nirvana every feeding starting with week two of bloom. SensiZym: 1.5 teaspoon every other feeding starting week three of bloom. Followed manufacturer’s dosing instructions for Voodoo, Tarantula, Piranha and discontinued those three additives at week four of bloom. Organic B: 1 teaspoon every other feeding through week 6. Bud Candy: 1.5 teaspoons per gallon every feeding from week three until flush.
Note that the above dosage recommendations are my personal customized organic marijuana feed program and are not in exact compliance with the Advanced Nutrients feed charts.
Nutrients solution pH: 6.1 Nutrients solution ppm: 300-570. (See discussion below)
Flowering Time: Blackberry Kush: 61 days. Skywalker OG: 60 days.
Flush: Six days with reverse osmosis water.
Total cost of nutrients actually used during a grow season that produced 2.5 pounds of premium dried 100% organic marijuana: approximately $187.
Results & Discussion
This was my first time growing all-organic. It took me several weeks to get used to the big differences between using synthetic hydroponics nutrients in a sterile, inert root zone media like rockwool as compared to all-organic feeding.
Growth rate in veg phase, and floral maturation rate in bloom phase were both about 15-25% slower than when I ran pure hydroponics for my marijuana feed program.
Total grams per watt were also slightly less than growing the same marijuana strains with pure hydroponics. This confirmed what I have been told before, that the one downside of going with all-organic or natural fertilizers and soil as compared to hydroponics synthetic nutrients and pure hydroponics marijuana growing is that you get slower growth rate and less harvest weight.
I chose Iguana Juice and the other Advanced Nutrients organic products after talking to hydroponics store staffers and other growers, talking to hydroponics manufacturers’ tech support, and looking at full range of non-synthetic nutrients brands and products used by marijuana growers.
From what I’ve seen look at various organic products sold to marijuana growers, most other “organic” fertilizer brands have problems with viscosity, smell, ingredients, quality control, performance, and cost.
I was also warned by my hydroponics store that some brands advertise “all-organic” products that contain non-organic materials. The warnings included Age Old Organics, General Hydroponics Floralicious, Superthrive, Earth Juice, and Pure Blend Pro (sold by Botanicare).
Note that pH and ppm are somewhat hard to measure using organic fertilizers for your marijuana. You have to clean the pH probe a couple of times while taking readings and before you put your probe back into a storage solution; in some cases it’s best to do an average reading.
Or, you can run a variable pH using 5.9 one feeding, 6.1 the next, and then 6.3 the one after that…then going back and starting at 5.9 again. That way, the average pH in your root zone is more likely to be in the 6.1 range, which I consider to be the best pH for organic growing.
Marijuana growers are advised to carefully monitor pH and ppm reading in organic feed programs, along with monitoring plants for signs of overfertilization and underfertilization, to achieve the best results.
The use of beneficial microbes as provided by Voodoo Juice, Tarantula, Piranha, and Mother Earth Super Tea (and feeding carbohydrates to those beneficials with boosters such as Bud Candy), is very important in an organic marijuana root zone. Beneficial microbes (and SensiZym) break down organic materials into forms that can be taken in by marijuana roots as nutrition. They also enhance marijuana root mass and root function.
Marijuana growers who run a partially organic feed program but also use synthetic nutrients salts (especially ammonium nitrate) run the risk of killing the beneficial soil microbes and making it harder for their marijuana plants to take in nutrients. Soil must have active microbial life if your plants are to intake nutrients efficiently.
Based on the grotesque smell of Earth Juice, Fox Farm, and some of the other organic products I looked at, I kind of thought anything organic was going to smell like crap.
So I was happily surprised that Iguana Juice didn’t have so much of an offensive smell. And the Mother Earth Organic Super Tea really does smell like black tea. You almost feel like you could drink it! And I was also pleased that someone finally figured out how to make an organic tea that holds its potency and bioactivity over time.
My marijuana plants didn’t have any nutrients problems except for a very slight yellowing at the leaf tips, which was most likely a slight nitrogen deficiency. Their leaves were a beautiful green, growth was steady, and bud development was as thick, sweet, and THC-loaded as I’ve come to expect from the two strains I grew.
The taste, aroma, and high were as beautiful and appealing as what I’ve come to expect from these two marijuana strains. I harvested the Skywalker OG “early” because it has a couchlock effect if you let it go too long.
Overall, I found organic growing to be easier than hydroponics growing, mainly because I didn’t have to worry much about ppm or nutrient burn. When I experimented by exceeding the recommended dosing of base nutrients and additives, my marijuana plants handled it fine. Of course, this could be because the two marijuana strains I grew are known to be hungry, heavy feeders.
There are other types of all-organic marijuana growing, including the True Living Organics method, the use of organic components to make supersoil, and the combining of synthetic and organic nutrients for marijuana. I intend to try those someday and write marijuana grow reports on them too. Happy Growing!