Healthy soil is the foundation for producing a cannabis crop that is potent and plentiful. Adding compost, monitoring and adjusting pH, and inoculating with beneficial bacteria and fungi are all ways to take your cannabis to the next level. However, the soil you begin with is the most fundamental factor in successful plant growth.
All soils are not created equal. Healthy soil is composed of quality ingredients and should be tailored to your growing needs. Are you an indoor, outdoor, or greenhouse grower? Are you starting with seeds and cuttings, or are you transplanting clones?
This article will take you through what makes a healthy soil, and what each growing method requires. We’ll also talk about how to customize your soil to further enhance your growth. Soil is more than the sum of its parts. For simplicity sake, here’s how it breaks down:
Healthy Soil = Organic Materials (Compost) + Minerals + Living Organisms + Air + Water
Organic Materials (Compost)
Organic materials are formed naturally through the decomposition of plant and animal matter. We usually refer to the final product as compost, in order to not confuse the starting material with what we’re looking for in a soil blend. If you’re curious about the science behind composting, check out Composting: the Basics and the Benefits.
Quality organic materials will:
- allow your cannabis plant to form better roots and protect those roots from pathogens
- increase beneficial bacterial populations and diversity
- boost cannabis plant growth by improving CO2 intake
Minerals & Parent Material
In The Importance of pH for Cannabis Growers, we talked about parent material – the type of rock material from which minerals are sourced. In a natural environment, rocks hold different minerals and slowly release them to the soil. The type of plants that can grow in any area depends on these minerals and their availability.
The two categories of minerals required for healthy plant growth are known as macronutrients and micronutrients. For a refresher, check out our posts on macronutrients and micronutrients. Organically sourced minerals are the best option for soil health, and fertilizers that are not organic or are missing micronutrients should be avoided.
A complete source of minerals will:
- help your plants fight stressors such as light, temperature and disease
- decrease the time cannabis plants need to mature
- improve flower yield and potency
From worms popping out on rainy days to tiny bacteria, living organisms are critical to great soil. When we have control of our soil, it can be difficult to replicate the complicated microbial ecosystems that co-exist with plants naturally. This is why understanding bacteria-root and mycorrhizae (fungi-root) relationships is vital for growers.
Diverse organisms in healthy soil will:
- protect your cannabis from disease and drought
- speed up growth through unlocking more nutrients from the soil
- improve flower yield and quality
Air and Water
Organic material, minerals, and living organisms will naturally create a soil structure with good aeration and moisture retention. However, you must still use clean unchlorinated water, follow growing instructions, and check for sufficient drainage. This will ensure that water doesn’t build up and displace the oxygen in the soil. An easy way to maintain a steady and optimal water-to-air ratio is to use BlueSky’s EazyGrow System.
An optimal air-to-water ratio will:
- improve microbial efficiency and nutrient availability
- protect your cannabis from anaerobic pathogens
- prevent nutrient loss
Poor Starting Soil
In contrast to the benefits stated above, a poor starting soil can be detrimental to a grower. Low-quality soils can lead to:
- A vicious cycle of oversensitivity to stress
- Nutrient lockout; when soil conditions prevent your plant from accessing the macro and micronutrients needed for healthy growth
- Poor-to-no yield in cannabis crop
Different Soils for Different Growing Conditions
Now let’s apply what healthy soil means to each of the three methods of cannabis growing.
This style of growing is perhaps the most difficult. Armed with the right knowledge, outdoor growing can reduce costs, have a smaller environmental footprint, and allow for natural plant development. Many growers claim outdoor growing results in a broader cannabinoid profile, allowing plants to reach their full genetic potential. Indoor and greenhouse growing techniques must rely on the manipulation of light and other conditions to accelerate growth.
Since the sunlight available to your plants is out of your control, the nutrients in your soil that are involved in photosynthesis need to be closely monitored. Keep an eye on the micronutrients sulphur, magnesium, and zinc to ensure your plants can make the most out of the sunlight.
Rain is another important factor when growing outdoors. Growers should start with a strong nutrient and microbial environment, creating a soil structure that will balance moisture retention and drainage. Using healthy soil from the beginning can prevent common pitfalls that lead to failed cannabis crops.
Indoor growing takes a hands-on approach. For growers looking to fine-tune their cannabis crops, this approach allows for controlled water and light conditions. These benefits must be weighed against the dangers of contamination and the increased costs in energy. In an enclosed environment, diseases can easily spread from plant to plant. Bio-inoculating your plants with beneficial microorganisms will help to prevent harmful bacteria and fungi from being able to damage your cannabis.
Greenhouse growing is a compromise that many growers love. This method reduces the expensive energy bills from indoor growing, while still allowing for fine-tuning and control.
Trapping the warmth of the sun to facilitate growing saves on costs and speeds up cannabis development. However, heat can fluctuate greatly in greenhouses, causing stress on plants within. To protect against temperature stress, choose a soil that is pre-fertilized to contain the perfect amount of zinc.
Infants, teens, and adults all have different caloric and nutritional needs, and plants are no different. While macro and micronutrients are required by plants throughout their development, the need for specific nutrients also changes over the growing cycle. For this reason, developing custom soils for the different stages of cannabis growth is a science and an art.
Soil additives can enhance soil even more than having traditional organic materials, minerals, beneficial bacteria and fungi. You can strongly increase yield by adding materials such as worm castings, bat guano, sphagnum moss peat, or coir dust.
Healthy Soil & BlueSky Organics
For most growers, BlueSky Organic’s Super Soil is the best option for healthy soil. Super Soil is bio-inoculated with beneficial bacteria and mycorrhizae, and contains a precise nutrient and mineral formula. It is also pre-mixed with the specialized additives we talked about previously. For growers looking for tailored solutions, BlueSky will even work with you to develop a custom soil blend.
However, Super Soil is not recommended for growing from seed or fresh cuttings. In this case, a propagation medium such as EAZY Plug should be used, followed by transplanting into Super Soil. The pot and sleeve-free Eazy Grow System removes the stress of transplanting and provides the ideal air-to-water ratio for seedlings. It is available for different scales of growing and introduces optimal nutrient blends for each stage of growth.
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