Cannabis is only as good as the soil it’s growing in. If you consider soil as an afterthought to your growing process, you’ll find some very noticeable problems come harvest time.
Healthy soil produces healthy plants, and as many organic soil advocates argue - a better-tasting product. Growing organically, in a well-built soil, is good for you and your buds.
What Is Organic Living Soil?
The best way to understand healthy, organic soil is to use a forest as an example. One the one hand, we have the Amazon rainforest, teeming with life, biodiversity, and a million different creatures making up a thriving ecosystem. It's loud with insects, birds, and rich in plant life.
On the other hand, we have a monoculture plantation with a single species of tree. Less diversity means fewer insects and fewer birds. This Monsanto style plantation is prone to disease and infestation, and eerily quiet.
What sounds healthier? Like the rainforest, you want to build soil with a powerful life-force. Its got many different organic components, including bacteria, fungi, and micronutrients. You can, of course, create a basic soil mixture without all these components, but your plant will suffer.
Plant life, including your cannabis crop, evolved in synergy with a diverse ecosystem. Who wants to grow lack-luster cannabis, when you can produce a premium crop by merely paying attention to the soil?
The 3 Fundamental Building Blocks in Organic Soils
- Organic compost
- Organic base material
Organic compost is pretty straightforward; its decomposed plant material created as organic waste breaks down.
What is an aerator? Aerators are perlite, vermiculite, and other options which fluff up the texture. They improve drainage and improves root development.
The organic base material is the substance, the grit of your soil. Its building blocks like coco fiber or Ancient Forest natural humus.
Of course, you can build your soil from the bottom up using equal parts of each of the three building blocks. Otherwise, if you live in a region with thriving cannabis cultivation, you can likely source some local soil options - all specially formulated for growing cannabis.
But this is only the base material. You need to build an ecosystem of biodiversity to really meet the needs of your crop. Quality soil has many different parts. For example, have you read the ingredient listing for any reputable organic soil brands? Check out what's on the back of Roots Organics soil mixture:
Coco fiber, peat moss, perlite, pumice, premium worm castings, bat guano, kelp, fishbone meal, soybean meal, feather meal, greensand, leonardite and alfalfa meal
What Are the Best Organic Soil Amendments Cannabis?
As you’ve just learned, great soil for growing cannabis is much more complicated than many beginner gardeners assume. To build healthy organic soil for cannabis, you have to understand the best soil amendments for cannabis.
Soil amendments are additions which improve the environment for the plant growing in it. Each kind of plant is going to need different amendments as a way to perfect the setting for an epic harvest.
Soil amendments improve the soil’s essential characteristics, like the texture and the pH level. As we discussed, the texture is crucial. A soil's physical structure can make or break a harvest.
Don’t be afraid to get your hands dirty and feel the texture. Does it feel thick, sandy, or like clay? Does it feel loose, fluffy, and organic? The texture shows you the drainage and aeration properties.
Best Soil Amendments to Improve Physical Properties
- Coco fiber
What about the pH level? Is it basic or acidic? Unless you already have an accurate reading, you’ll have to test the soil yourself using either a simple pH test kit or a digital reader. Once you have the results, you can correct if needed by adding various soil amendments.
But what is the correct organic soil pH for cannabis? Cannabis prefers a pH level between 6 to 7.
Best Soil Amendments to Improve the pH
- pH Level Up
- pH Level Down
What Are the Best Organic Nutrients for Cannabis Plants?
Just like humans, all plants need nutrients to survive. Also, just like humans, plants need more than just the macronutrients. To make sure your cannabis plants thrive, you also need to provide a range of micronutrients.
The best organic nutrients help build a specialized soil profile suitable for cannabis. If you are growing tomatoes or dailies, you’ll need to create a slightly different nutrient profile. With that in mind, look for nutrients designed specifically for cannabis, and furthermore, for each stage of growth.
Nutrient labels include a ratio of nitrogen to phosphorus, and potassium or N-P-K. Cannabis prefers the following ratios depending on its stage of growth:
- Seedling/Clone: 5-3-4
- Vegetative: 5-2-3
- Flowering: 5-5-3
Keep in mind different nutrient brands may vary slightly in these ratios, but should follow the same pattern.
If you want to add organic soil amendments to improve these macronutrients consider the following:
- Nitrogen Rich Soil Amendments: worm castings, crustacean meal, Guano
- Phosphorus Rich Soil Amendments: bone meal, chicken manure, and glacial rock dust
- Potassium Rich Soil Amendments: Compost, seaweed meal, and wood ash.
Sound overly complicated? Start measuring your nutrient levels through run off or a slurry — check out this guide for more information.
Or, if you still want to maintain a healthy nutrient ratio without any complicated math, look for all-in-one nutrient kits. They've taken the guesswork out of this process and provide everything you need from seedling to harvest.
What Micronutrients Does Cannabis Need?
Many cultivators may want to ignore the micronutrients, but they form a crucial piece of the cannabis-growing puzzle. Cannabis (like all plants) require secondary or micronutrients - just like we humans need trace elements in our diet.
Micronutrients for plants include the following (listed in descending order of importance):
Sound like too much? Good news! By the time you have built your soil, added the various organic amendments, and reached this stage of development - very likely your soil has most if not all of these secondary nutrients.
That said, some cultivators like to get into the nitty-gritty, including adjusting the levels of these often-ignored nutrient levels.
If this sounds like you, don’t be afraid to go ahead and work with secondary nutrient soil additives, like General Organics Calcium-Magnesium blend. With a little experimentation, you can see how adjusting these minute levels of compounds affect flower development.
What is Organic Living Soil for Cannabis?
Up to this point, we haven’t discussed the living aspect of our thriving cannabis ecosystem. Cannabis, when grown in soil, actually develops an intimate two-way relationship with this environment.
Through the cannabis roots, your plants uptakes oxygen, water, and nutrients. The roots build a complicated network of connections with the bacteria and fungi living in the soil. Focus on building a healthy bacteria and fungus population, and you make it easier for the plants to pull these essential resources from the soil.
Furthermore, if you have an eclectic microscopic community of living organisms in your soil, they can help improve the health of the plant. With the right fungus and bacteria populations, they help the plant fight off pests and diseases.
To build a thriving microscopic support system - try adding the following soil amendments:
- Fungus additives: Kelp meal, Humic acid, Mycorrhizal inoculant
- Bacteria additives: worm castings, bat guano
What Is the Best Organic Soil for Cannabis Seedlings (and All Stages)?
If you’ve made it this far, you have successfully created a super soil for cannabis. It’s all-natural, all organic, and going to give your plants the boost they need to produce big, beautiful harvests.
Let’s review the fundamentals of organic cannabis soil:
- The best organic soil for cannabis is built on equal parts of compost, aerators, and organic base material.
- Cannabis prefers an organic soil mixture with a pH havering between 6 and 7.
- Nutrient requirements for cannabis change slightly during each stage of growth. Seedlings need higher nitrogen and lower phosphorus needs (ex: 5-3-4). Your plants need higher nitrogen and even lower phosphorus and potassium in the veg stage (ex. 5-2-3). Flowering needs equal parts nitrogen and phosphorus plus lower potassium (ex. 5-5-3).
- For an added boost, work with trace elements like Calcium and Magnesium.
- Add a few bacterial and fungus inoculants to finish off a thriving cannabis ecosystem.
As you get started, work with soils, amendments, and nutrients specially designed for cannabis. As you get acquainted with using these pre-mixed kits, you’ll see their impact over your harvests. Eventually, you’ll get comfortable making custom soil mixes, playing around with inoculants, and experimenting for better, tastier yields.