Having the best soil is a critical component of your cannabis growing season. If you have the wrong soil, you may have considerable problems.
That said, finding the best soil for cannabis growth is never straightforward; there are hundreds of soil products on the market. So, if you don’t know what to look for, you may have a difficult time finding the best soil.
But don’t worry; in this grow guide, we will help you find the best soil possible for your cannabis plants.
Autoflowering Seeds Vs. Feminized Seeds
Many new cultivators wonder whether they should source different soils for autoflowering and feminized seeds. Although the best cannabis soils work well with either seed, there are some exemptions.
Autoflowers prefer a light mixture with fewer added nutrients. Therefore, keep autoflowering seeds away from heavily fertilized soils, such as clay.
Also, you should start photoperiod plants in small pots with soil that has little nutrients and replant them after a few weeks. More mature plants can tolerate more nutrients than seedlings.
Having said that, a good soil can work well with both autoflowering seeds and feminized seeds. So much so, that many growers will use the same soil with either seed.
Common Traits Among Good Cannabis Soils
Unfortunately, not every soil is suitable for growing cannabis. What’s more, not all cannabis requires the same soil type. Choosing the best soil depends on the climate, the cannabis you’re growing, and whether you’re growing it in the wild or at home. However, there are some common traits among all cannabis soils:
- Texture: Cannabis often likes a loose and light soil texture because a light texture ensures more oxygen reaches the roots.
- Drainage ability: Cannabis soil must have tremendous drainage ability. If not, your plants will become sick and provide poor yields. The water should not pool on top of your plants.
- Water retention: Although drainage ability is critical, water retention is also essential. Excellent cannabis soil has the perfect balance of both.
- pH value: The ideal soil for cannabis has a pH level of around 6.0, or a pH of 5.8–6.3. If your pH level fluctuates outside this range, you’ll have poorer yields, and your cannabis plants may die.
- Nutrients: Like all plants, cannabis plants require plenty of nutrients from the soil. Thankfully, most soils are already nutrient-dense. However, these nutrients only last for up to one month. You should begin to add nutrients after this. Your soil will need organic substances—such as compost, worm castings, or guano—if you’re growing without additional nutrients.
Which Soil Mixture Works Best for Cannabis Seeds?
1. Sandy Soil
Sandy soil works well with all Cannabis Seeds because it’s coarse and offers excellent drainage. However, it does have poor water retention. When you water sandy soil, various nutrients—including nitrogen—wash away. Despite that, sandy soil offers low pH, keeps your soil airy, has high oxygen levels, and is easy to use.
2. Silty Soil
If you’re looking for soil rich in minerals and organic particles, silty soil is your best friend. Silty soil has incredible water retention, yet it also offers superb drainage. Silty soils are also simple to use and medium-coarse.
3. Loamy Soil
Loamy soil is one of the best soil types for growing cannabis because it provides maximum drainage and water retention. It’s also high in oxygen and nutrients. However, loamy soil is often expensive, so it’s not ideal if you’re on a strict budget.
4. Clay Soil
Although clay is a heavy soil that’s not always easy to work with, it’s superb for most Cannabis Seeds because it’s very rich in minerals and nutrients. However, although clay soil holds water well, it has poor drainage.
What Are the Signs of a Good Soil?
- A good soil will have perlite and coco already added to it.
- If your soil has worms, this is a good thing because worms aerate the soil.
- A good soil brand will state its N-P-K values, such as amount of compost, perlite, trace elements, etc.
What Are the Signs of a Bad Soil?
- Bad soil will have an unpleasant smell; this means bacteria is likely present. Keep this away from your cannabis.
- The soil will feel dense and heavy because the drainage is poor.
Making Your Own Soil Mixture
If you’ve just started growing cannabis, getting ready-made soil from the grow store might be the best choice. Top-quality cannabis soil—from a reputable store—often has everything your plants require in perfect ratios.
Yet, in some cases, it’s an excellent idea to make your own soil mix instead of purchasing a mixture from stores. Some ready-mixed soil may be too high in nutrients, such as nitrogen.
This soil mixture contains adequate nutrients and can boost the aeration of the soil medium:
- 3 parts compost
- 3 parts peat moss
- 2 parts perlite, pre-wet
- 1 part vermiculite, pre-wet
However, it’s important to go easy on the fertilizer when using autoflowering seeds because they are compact and short. As a result, they don’t require additional nutrients. Autoflowering seeds, however, need aerated soils for optimum root oxygenation.
Soil Substrates To Add to Your Cannabis Soil
1. Coco
If you add a 25-50% ratio of coco coir to your cannabis soil, your soil will become lightweight and airy, which is perfect for autoflowering seeds. By adding coco to soil, you’ll enhance the air pockets and encourage a mass expansion in the rhizosphere. The best advantage of adding coco is it’s an inert growing medium.
2. Biochar
Biochar is excellent for autoflowering seeds because it offers incredible water-holding capabilities, has a massive surface area, and it’s a pure carbon source. You can make biochar by heating wood to very high temperatures, whereby you begin to see a small, charcoal-black crystalline substrate. Organic farmers love using biochar because it’s 100% carbon and has a shelf-life of thousands of years.
3. Perlite
Perlite is popular for cannabis growers because it improves drainage while holding a specific amount of water. If your soil is too heavy for your preference, adding perlite is an excellent way to improve aeration and drainage. Many growers find perlite-rich mediums superb for cannabis seed germination or cuttings.
4. Vermiculite
Vermiculite is a natural mineral made from magnesium, aluminum, and silicates. Many growers will use vermiculite to keep their roots moist for longer. Thankfully, vermiculite is simple to blend with soil and other additives if you’re making a soil mixture.
5. Clay Pebbles
Although many cannabis cultivators are familiar with clay pebbles as part of a hydroponic setup, they aren’t aware you can also use them to improve soil quality. By adding clay pebbles to the bottom of your raised beds and containers, they can assist with drainage and prevent water from pooling.
Final Thoughts
Although cannabis soil may seem complicated on the surface, with this guide, you can find the best soil to match your requirements. Remember, your soil is incredibly important; without good soil, it’s hard to grow good cannabis.
0 
