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A Guide To Choosing the Best Soil for Growing Cannabis

By Last updated on April 30, 2024Last updated on April 30, 2024No Comments

Growing weed plants in soil is considered by experts as an easy way to create high-quality crops of great flavored buds.

The ideal soil for growing weed plants needs to perform many crucial functions to enable optimal growth of the roots and rest of the plant. These functions include controlled water retention, balanced nutrition, an optimal pH, and proper drainage.

The variety of soil available to consumers is vast and ranges from cheap options in supermarkets to expertly crafted and expensive soil blends. Some soils are better for creating a cannabis garden than others.

Traits for proper soil

Traits for proper soil

After you have settled on which plant genetics you want to use, the next step is to choose your grow medium. This is not necessarily an easy task as there are many different options to choose from.

For those that choose to grow with soil, there are some traits to consider when deciding which type of soil is best for your garden:


Heavily compacted and dense soil is not good for growing weed plants. Light and airy mixes tend to be better for cannabis. Lighter soils enable proper levels of root oxygenation which is vitally important for roots to thrive.


Proper water drainage is also important. Soil that is waterlogged leads to unhealthy roots and will subsequently hamper growth. A sign of poor drainage is if you water your plants and pools of water start to form on the surface.

Water retention

You want your soil to be able to drain properly but you do not want it to drain too much. Retaining a proper amount of water will assure that your roots and plant will not dry out.

pH value

A soil pH of 5.5-6.5 is ideal for weed plants. You can buy tester kits to determine your soil’s pH level. Maintaining a slightly acidic pH allows weed plants to take in nutrients like nitrogen, phosphorus, and potassium, which are all necessary for the growth and flowering of weed plants.


Many soils contain a solid level of nutrients. Eventually, these will become depleted and the grower will have to reinvigorate the plant with added nutrients. The three main nutrients for cannabis are Nitrogen (N), Potassium (K), and Phosphorus (P). Other crucial micronutrients are also required.

Certain growers prefer to use the soil from the ground which naturally contains many of the micro and macronutrients that cannabis needs to thrive.

What to look for with natural soil

Potting soil mixes from the store contain certain elements and nutrients for growing cannabis. Natural soil outside can contain these elements and more. However, before you go out and place your plant into the dirt, you should first learn what makes natural soil either good or bad for weed plants.

There are four varieties of natural soil: sandy, silty, loamy, and clay. Most soils will consist of a blend of these 4 types which can make for unique soil types.


Sandy soil has good drainage and is coarse. The water retention in sandy soil is poor. Nutrients such as nitrogen can be washed away quickly when your plants get watered. Sandy soil is a viable choice for growers and is easy to work with.


Silty soil is loaded with minerals and organic materials. It is a medium-coarse soil type that has good water retention while also having decent drainage. This is one of the most fertile soil types due to its minerals and organic substances.


Loamy soil combines silt, clay, and sandy soils and adds extra organic substances. It is possibly the best type of soil for growing weed because it has ideal water drainage and retention, and is chock full of oxygen and nutrients.


Clay soil is heavy and therefore is not the easiest to work with. It retains water incredibly well but has very bad drainage. It is loaded with minerals and nutrients, making it a great option to mix into other soil types.

Organic potting soil for weed plants

Beginners and professional growers alike can start on the right foot with pre-made cannabis potting mixes. Everything that your plants want is in these mixes. They contain vitamins, beneficial bacteria, macronutrients, micronutrients, fungi, and much more.

Compared to the hyper-accelerated growth of hydroponics or aeroponics, soil mixes that are cannabis-specific provide a natural form of growth.

Fox Farm’s Happy Frog Potting Soil

Fox Farm’s Happy Frog Potting Soil is considered to be one of the best organic cannabis soils available on the market. This highly rated soil is perfect for young plants and seedlings thanks to the mycorrhizal fungi and other beneficial microbes that it contains.

The source of the nutrients in this soil comes from earthworm castings, bat guano, earthworm castings, and broken down materials from forests such as wood chips. This mix hosts enough nutrients to take you through the entire cycle of your plant’s life.

Unlike Fox Farm, many other soil brands tend to make “hot” soil mixes. This means that they put an overabundant amount of nutrients into the mix.

Especially for beginners, this is one of the best potting soil mixes for weed plants. This includes seedlings, which do not need a high nutrient level.

Nature’s Living Soil Organic Super Soil

Nature’s Living Soil Organic Super Soil has the goods to last you for the duration of the growing cycle. This soil is very simple and user-friendly: just plant and water. For first-time growers, this is one of the best soils you can buy.

The term “super soil” generally describes a neutral organic soil base that was enhanced with a range of added microorganisms and nutrients. Super soils make adding liquid nutrients to your plants redundant.

Red’s Premium Biochar-Based Soil

Another all-in-one soil is Red’s Premium. Its stand-out feature, biochar, is what makes this one of the best soils for cannabis growing. Biochar is an amendment that excels at promoting and protecting bacteria growth, fungi, and other essential microorganisms for root development and immune system strengthening.

Biochar, a carbon charcoal amendment, mediates your soil’s nutrients and the water you feed it. It provides microorganisms with a large surface area to thrive.

Aurora Innovations Roots Organics Formula 707

Roots Organics Formula 707 is a versatile option if you are planting your cannabis plants in a large container outdoors. Designed to have great water retention, Formula 707 contains beneficial microbes and other ingredients that are suited for larger containers.

Formula 707 is a highly customizable soil with less perlite, less pumice, and fewer amendments than other soils. This customization allows you to add liquid nutrients and topsoil at different growth cycles depending on the plants’ needs.

10-14 days is how long the nutrients in Formula 707 will last before you have to add anything.

Purple Cow IndiCanja Organic Living Soil

Purple Cow IndiCanja is one of the more modern soils on this list. This natural, plant-based organic soil mix is filled with essential nutrients and minerals to get your seedlings started. This soil is great for all cycles of plant growth, from seeds to flower.

IndiCanja advertises their soil as “by growers, for growers.” This all-in-one soil is great for beginners or experienced growers.

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