For’ve got to nourish to flourish, and it all begins with the roots or base of your plants. Using soil is one of the most popular growing mediums, and is ideal for beginner growers. But, choosing the right or best soil for marijuana is key. The type of cannabis soil you choose can not only affect your plant’s life cycle of growth, but your end yields at harvest time too. So, what is the best soil for growing weed? We’ll answer that question and more in our in-depth guide to the best soil for cannabis growing.

The Pro’s and Con’s of Growing in Soil

Small cannabis plant in soil

With the emergence of hydroponic growing, many cannabis growers are now asking - to grow in soil, or not to grow in soil? Like many of the factors that go into growing healthy marijuana plants, your soil is just another that will be just as important to choose. Of course, there are pro’s and con’s of going with cannabis soil as a growing medium, so we’ve compiled a simple breakdown to best understand.

Pro’s of Growing with Soil

Hydroponics systems can be expensive, so the first advantage of growing in soil is the simplicity and cost-effectiveness. Plus, it’s likely you have prior knowledge of how to grow in soil since most plants besides cannabis are grown in such a way. The ease of growing in soil is ideal for beginner growers, which is why it’s more popular than most other growing mediums. Overall, soil is easier to maintain, more forgiving with any mistakes and can help boost the flavours of your final product, too.

Con’s of Growing with Soil

With dirt, comes pests, so that’s the first major con of growing in soil to consider. Soil is perfect for detrimental pests to hide and thrive in, so if going with this method you’ll want to ensure you’re buying new and clean bags of the type you choose. Additionally, soil can lead to slower growth when compared to hydroponics and can be hard to manage with big bags, and mixing balanced ratios. Last but not least, hydroponics are known to produce higher yields which is a con for many when choosing to grow with soil.

Factors to Consider when Choosing a Soil

small plant in soil

To figure out which is the best soil for marijuana, you should understand the factors that soil lends to the health of a growing plant. To create an optimal environment for growth, soil traits that should be considered include -

  • Texture
  • Drainage
  • pH Value
  • Water Retention
  • Nutrients

Types of Soil

Once you decide to cultivate using soil, that’s not the last decision you’ll have to make. Then, it’s time to choose what type of soil is best for your operation or the growth you’re trying to achieve. Luckily, over the years, the growing community has learned what works and what doesn’t. So, using this knowledge can help boost success from the start. The most popular types or textures of soil include -

  • Sandy soils - Sandy soils contain lower levels of pH which will help you along the way when balancing pH for nutrient uptake. Higher oxygen levels also make sandy soils, helpful for optimal growth. The granules are larger so sandy soils also help promote proper drainage and avoids compactness. On the flip side, better drainage means less water retention and can lead to sandy soils drying out more quickly than others.
  • Silt soils - Silt soils have a smaller granular size compared to sandy, so conversely it retains water better, with less than ideal drainage. But, it naturally contains beneficial nutrients which can help stabilize plants for a more healthy growing environment.
  • Clay soils - Clay soils are the smallest in granular size in comparison to sandy, and silt, but comes with a higher pH level than most. It’s consistency may be hard to work with, but the material has a high level of beneficial minerals that promote healthy growth. Again, like silt, it retains water better than sandy soils, yet lacks in drainage.
  • Loam soils - So, what happens when you combine soil types to benefit from the varying types' individual advantages? That’s the purpose of loam soil. Cannabis plants flourish with mixed materials like loam soils provide. Due to the soil’s neutral pH levels, fertile nature, high oxygen levels, and ideal drainage and retention. The only downside, is loam soils can be more expensive in cost.

Soil Additives to Consider

After you’ve decided which soil to purchase, if it’s not a combination made specifically for growing weed - you can easily add materials to improve the base’s quality. Soil additives can improve drainage, increase water retention and the uptake of nutrients for optimal growth. The most popular items to add to soil, to do so are -


Perlite is white pebbles in varying size, that feel like styrofoam in consistency. When adding to soil, they help improve overall texture by better holding water and air. Perlite also helps improve drainage when using 10-20% in your soil mix.

Coco Coir

Coco Coir is a unique material that’s made of coconut husks. The consistency helps promote ideal water retention without causing the soil to become too heavy. Coco Coir’s biggest advantage is it helps the root of your plants develop more quickly. It is possible to grow your plants in strictly coco coir, but the soil can be costly. If creating a blend of soils, it’s recommended to add up to 30% of your final mixture.


Vermiculite is often used with perlite, and are similar in shape and color. The additive lightens the weight of the soil, while improving water retention.

Clay Pebbles

Clay Pebbles while often used with hydroponics, can also be added to your growing containers for unique benefits, too. Most growers place clay pebbles at the bottom base of their cannabis soil, which prevents water from pooling. This enhances overall drainage, and avoids root rot that can occur from poor drainage. Other growers add clay pebbles to the top of their soil mix, to trap moisture that would normally escape through evaporation. On top, clay pebbles also serve as ‘mulch’ hindering weed growth, and protecting beneficial nutrients from hot sun or lights.

Worm Castings

Worm castings...or, yes, worm ‘poop’ is a highly beneficial soil additive used by a variety of gardeners and growers. It can help cannabis soil by enhancing the overall texture for better water retention and drainage. Worm castings, and other ‘icky’ materials like manure or compost naturally also contain beneficial nutrients like phosphorus, potassium, and nitrogen that slowly release over time.

Photoperiod Plants vs. Autoflowering

Of course, keep in mind that photoperiod plants will require differing soil content versus autoflowering plants. That’s because autoflowers require fewer nutrients overall for optimal growth. Plus, autoflowers are more finicky to stress, and high levels of nutrients can actually burn the seedling or early veg plants.

When mixing soil for autoflowers, an ideal mix to implement would be -

  • 3 parts peat moss
  • 3 parts compost
  • 2 parts perlite or coco coir
  • 1 part vermiculite

Best Recipe to Mix Your Own

There are many viable options for purchasing a ready-made mix of soil, specifically formulated for cannabis. But, when you make your own you can pick and choose which factors are most important to the health of your crops. If you’re looking to experiment with mixing your own soil, below is a simple base of ingredients you can follow for success.

Making your Own Cannabis Soil Ingredients -

  • 1 part potting soil – a high quality soil for the base, is recommended.
  • 1 part compost – you can purchase compost, or make your own at home. Adding worm castings with your compost is highly beneficial, too.
  • 1 part perlite or coco coir
  • 1 part vermiculite

Soil Matters for Growth

Overall, once you understand the in’s and out’s of how growing in soil works - it’s by far, the easiest and highly effective grow medium to implement. With the information you’ve gained today, now you can start your crop off on the right foot, with the best soils for growing weed. The more you learn about the factors and environments that can affect your operation, the better your plants can thrive.