The Best Growing Mediums for Marijuana

There are three effective growing mediums used when growing cannabis. These mediums will ensure you have the optimal growing environment for your cannabis plant, from the seedling stage all the way to the flowering stage. The best growing mediums for cannabis are Rockwool, coco coir, and soil. In this article, we will explore all the variations of the growing mediums in-depth so you, the grower, can decide which one is the best option for you.

What is a growing medium?

The material, also known as the substrate, that you grow your marijuana plants in, is known as your growing medium. This is the actual substance you would put your seedlings in for the seedling to grow into big plants. There are many different types of growing mediums for the many different types of plants. As we are marijuana enthusiasts, we thought it would be important to share our favorite types of growing mediums that are used for marijuana plants. These mediums, combined with the best canna nutrients and growing systems will result in the biggest yields and densest buds.


Soil is the most popular medium to grow cannabis. This method is not as labor-intensive as the other methods we will mention. One of the major benefits of growing in soil is that most commercial soils you buy are optimal for the first 3-4 weeks of your growing cycle. That helps you because for the first couple of weeks you can focus on your watering strategy and not on which nutrients your plant requires. A good watering strategy is just as important as the nutrients your plants require. You can always combine soil with perlite and some coco coir to get more optimal growing conditions.

Soil is the most common medium to grow cannabis.

There are many advantages of growing marijuana in the soil for beginner growers as it is the most organic method. In the soil medium, you are able to control the pH level and nutrient levels easily as they don’t fluctuate as much as some of the other growing mediums. Your equipment is fairly basic so if you have a green thumb, you will find ease in growing marijuana. When grown in soil, marijuana buds have even proven to have a stronger smell and taste.

Although there are many positives in growing with the soil medium there are some downsides as well, like the fact that when you grow in soil, you are more susceptible to pests, mold, and fungus developing. This method can also produce lower yields compared to some other, more advanced, growing methods.

Coco Coir and Perilite

Coco coir is made from coconut fibers from the coconut’s husk and perlite is made from expanded volcanic rock. Using the coco coir and perlite mediums requires more of an understanding of nutrient balances than soil. These mediums lack nutrients and therefore you are solely responsible for the nutrients that the plant requires. This can be a major advantage if you are looking to have full control over your plants’ nutrient intake.

Coco coir is made from coconuts.

Coco coir is a soilless growing medium that is most similar to growing your marijuana in the soil as it has a natural pH level of 6.5-7 which is similar to unfertilized soil. This medium is very light and airy, this is great as it means a lot of oxygen will reach your plants’ roots. Adding perlite to a coco coir medium will also increase aeration and will help promote drainage.

Coco coir and perlite combinations are particularly loved by indoor growers as the preferred indoor growing medium. The reason is also the medium has a low chance of bug infestations allowing the plant to thrive. Using this medium is a low cost and effective way to get big yields, in a shorter amount of time.



This medium is one of the best growing mediums for hydroponics. Many growers choose this medium when they’re growing their cannabis in hydroponics as it is very absorbent and retains water very well. This medium comes in different sizes for the different stages of the growing cycle. The reason many growers prefer this method as it is an undisruptive medium for the different stages of your cannabis’ growing cycle. When your seedling has outgrown the small cubes from the first stage of growing, simply place the cube in the next size up.

Rockwell cubes are perfect to grow in hydroponics.

This considered a very advanced method as there is a lot more preparation that goes into Rockwool beforehand. Untreated, Rockwool’s pH level is 7.0 -8.0. This level of alkalinity is too high for cannabis to grow healthily. You will have to soak the Rockwool in distilled water (purer than tap water) test and adjust the pH levels until it reaches the 5.0 pH level. Make sure it doesn’t drop below the desired 5.0 as the Rockwool will then be too acidic, resulting in your plant having deficiencies. When handling Rockwool, you will want to wear protective gear as the fibers can irritate your skin, eyes, and lungs.

This medium is similar to coco coir as it doesn’t have any nutrients in it and you will have to make sure that you are giving the plant all the nutrients it needs to grow into a big plant with lots of dense buds. A major advantage of using this medium is the fact that this is a very sterile method of growing your marijuana plants and therefore there isn’t the risk of pests and disease of your plants. When using this medium in a hydroponic system, it will push your plant to great lengths which in turn results in bigger plants. This medium also allows greater aeration of your plant which results in extremely high yields and dense buds.


The different mediums we have discussed will all have different results for your plants. If you are a beginner, definitely start with the soil medium and master the art of growing marijuana effectively. This will help you later on when you are looking to start on the more advanced methods of growing marijuana. You may consider adding some perlite to your soil to achieve even greater results. When using the best seeds and the best canna nutrients for your plants you will get amazing results!

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