The following recipe is not ours, but it is what we have found to work best for most plants. All credit for this recipe goes to Clackamas Coots. First and foremost, it is important to keep in mind the quality of the inputs as 1/3 of this mix is compost and not all compost is as beneficial as you may think. This is one area not to look for the cheap alternative.
Making Coots Soil Mix
Let’s go over the recipe and then we can further discuss the best sourcing of the inputs.
Base:
- 1/3 Compost (or learn how to make your own compost)
- 1/3 Sphagnum Peat Moss
- 1/3 Aeration (Such as pumice stone, rice hulls, lava rock)
This will make up your base. For example, if you are trying to make 15 gallons of soil (2 cubic feet) you would add 5 gallons of each and then mix thoroughly.
Additional Inputs:
With the additional inputs, you will want to use a 1/2 cup of each per cubic foot of soil you are making.
- Neem/Karanja Cake (learn more about neem/Karanja cake here)
- Kelp Meal
- Crustacean Meal (learn more about crustacean meal here)
Minerals:
For the minerals, you will want to use a total of four cups per cubic foot. Therefore, you will use one cup of each of the below ingredients in your soil mix.
- Basalt
- Glacial Rock Dust (learn more about glacial rock dust here)
- Gypsum (learn more about gypsum here)
- Oyster Shell Flour (learn more about oyster shell flour here)
As mentioned earlier, it is very important to ensure you source quality inputs. The best compost would be homemade. If you are not able to make your own or just don’t want to, Malibu Biodynamic compost is the next best option. Sphagnum peat moss does vary from peat moss and it is best to ensure you are sourcing sphagnum peat moss. The aeration portion of the base isn’t as important, but you do want smaller chunks of lava rock or pumice stone. Incorporating rice hulls is advisable because once they break down, they are a great source of silica. Because they do break down over time, you don’t want your aeration portion to be made up entirely of rice hulls.
Please note you may find yourself needing more or less of the above inputs based on your grow setup.