1-844-807-1234 Menu Seeds

The Souvenir Seeds People

Shop Now!

Using Coco Coir as the Grow Medium for Your Cannabis Crop

Individuals new to growing cannabis may feel overwhelmed, as the process involves more than simply putting the pot seeds into soil. There are several growing methods to choose from, hundreds of strains, and multiple grow mediums. So much to consider!

Let’s start with grow mediums. There’s soil, coco coir, peat moss, hardened expanded clay, rock wool, and more! A popular choice for growers is coco coir. So, what is coco coir, and what are the benefits of using it?

What is Coco Coir?

Otherwise known as cocopeat, coir peat or simply coco, coco coir is made by grinding up coconut seed husks. The resulting substance is a biodegradable and renewable substrate that serves as an effective grow medium. An added benefit of coco coir is its reusability—it can be reused multiple times before being replaced. The general recommendation is to reuse coco coir three times.

In the past, the coconut husk was largely considered useless. Once the coconut seed’s flesh and juice were used, the rest was thrown away. Later, however, people began to see that the husk had many uses in the making of floor mats, brushes and mattresses, and in the making of gardening substrates.

What Makes this Material Ideal for Cannabis?

Billions of coconuts are harvested and processed each year across the globe. This fruit is native to many countries including the Philippines, India, and Sri Lanka. Furthermore, the fiber holding the coconut shell can be used in a wide variety of ways, including to make ropes and insulation. Now, cannabis growers from Alaska to Florida are discovering it can be of benefit to them as well.

When finely ground, coconut seed husk looks, feels, and acts much like soil. To obtain coco coir, the husk (coir) must be removed, soaked, and softened. This process may be done in tidal water. If this is the case, the salt absorbed by the husk will need to be removed. Once soaked and softened, the husk must be dried.

The drying process takes more than a year. Upon completion, the coir is organized into bales. Each bale is chopped and processed into one of three types: pith, fiber, and chips. Knowing the key difference between each type of coco coir is important for weed seed growers interested in the substrate.


Coco Coir Types


For those who are considering using coco coir as their indoor growing substrate in Vermont or Oklahoma, three types are available. Select either pith, fiber, or chips. Many who have tried all three consider pith the best when it comes to cannabis plants. Why?

Pith provides a texture that is most like peat moss. The main difference that will be noticed is the color, as coco coir pith is a rich brown. Its lightweight texture adds volume to any grow medium while improving airflow. As a result, cannabis plants’ roots have more space to absorb water. Simply add ~ 15 – 20% Perlite into the coco coir to increase the cannabis yield. Take care when using pith. If the manufacturer has not properly aged the pith, salts are let out that damage the plants. Choose the manufacturer of the coco coir pith carefully to avoid problems.

Coco coir fiber is stringy in texture, and this is what allows the oxygen to enter the root area. Water absorption can be increased by mixing coco pith with other substrates. One issue seen with coco coir fibers is that it tends to break down quickly. This can lead to air pockets collapsing, resulting in compounded substrate pressing on the roots over time. If the plants display symptoms of stress, the breakdown of these fibers may be the issue.

Coco chips, in contrast, are small chunks of coco. These are mixed in with other substrates to create air zones in the root area. People who have been growing cannabis for some time often choose to mix soils and substrates to create their own formula. Coco chips often come in large bales that novice growers find intimidating, challenging, and/or cumbersome. So, new growers may benefit from pre-mixed substrate to reduce the workload involved with creating a good grow medium.


Why Should a Grower Choose Coco Coir over Soil?

Coco coir, unlike soil, holds water and nutrient solutions like a sponge. Additionally, when planted in coco coir, airflow reaches the plant’s roots more readily than it does with soil. Optimizing plants’ access to water and nutrients is a massive perk when using coco coir.

Coco coir is an inert medium. While it does provide some potassium and phosphorus for the plants, growers find it does not offer much additional nutritional value. It comes with a pH between 5.6 and 6.2, which is ideal for cannabis plants. Nevertheless, nutritional supplements will be needed for each stage of a plants’ development.

Coco coir has a woody-like structure. This structure is made up of two-thirds carbohydrates and one-third lignin, and creates the ideal breeding ground for microorganisms that benefit the plant. The microorganisms also introduce rhizobacteria, a helpful bacterium, into the plant’s root zone. While nutrients, oxygen, and water are necessary, bacteria and microorganisms are responsible biodiverse root-level activities that the plant also benefits from.

Bacteria and microorganisms break down the cellulose found in the coconut husk fibers before converting cellulose into carbon. The carbon is then used to feed not only the plant but also the microorganisms.

Scoop up a handful of coco coir and feel the difference. As coco coir is less dense than standard potting soil, it will feel much lighter. It is light and almost fluffy thanks to the increase in surface area.

Potting soil, on the other hand, is dense. It also tends to clump together, and this reduces the amount of water that reaches the roots of the plant. When plants receive more water, they also receive more oxygen, and grow bigger, healthier, and faster.

Most growers know what an important factor humidity plays in successful cultivation efforts. What is also important is the quality of water supply, how it is held in the grow medium, and how well it is absorbed by the plant’s roots. Coco coir holds water while its lightweight texture does not limit the amount of water reaching the roots. With soil, its density and weight often squish the roots which can restrict a plant’s access to water and its vital oxygen supplies.



Growers who choose to make use of coco coir need to provide their plants with nutritional supplements because coco coir is relatively inert, providing only a small amount of nutrients. Care must be taken to select a nutritional solution designed for plants growing in coco coir.

The first thing to consider when choosing a supplement is the amount of potassium and phosphorus found in the mix. As a result, some growers choose a mix that contains less potassium and phosphorus. However, additional nitrogen will be needed for the microorganisms found in the root area.

Furthermore, consider the amount of chlorine and sodium found in the mixture. Too much is not good for the plants. Professional coco coir producers wash the elements out of the mix before selling it.



One major benefit of choosing coco coir as the growing medium is that it can be used several times before being discarded. Simply flush it and reuse it up to three times.  After the third use of coco coir, the growing medium needs to be replaced as it does break down and will not provide the proper environment for the plant’s roots and overall development.

Fortunately, coco coir is less ecologically damaging compared to other soil-less grow mediums. The average coconut tree produces 100 coconuts each year. Compare this to peat moss which takes 25 years to grow in a bog.

Pest Control

Unlike conventional soil, pests are rarely an issue when coco coir is used. They typically are not attracted to this substrate. As a result, growers will experience fewer pest-related problems.


When coco coir is used as the growing medium, plants tend to thrive. This applies to not only the plants but also the size of the flowers. While hydroponic systems produce better yields than both soil and coco coir, the coco coir has a definite advantage over conventional soil and peat.

Additionally, caring for a cannabis crop grown in coco coir is easier than crops grown in soil. The extra oxygen in the roots is one reason why this is the case. Good moisture levels also ensure that watering is less of a chore.

When comparing the various growing options, people typically look at coco coir as a mix between growing a crop in soil and using a hydroponic system. The natural fibers are more forgiving than a full-hydro system. In addition, they respond much better to nutrient changes than soil does. On account of this, plants grow faster and bigger, providing a crop that is up to ~25%more productive than soil-grown crops.

Choosing a Coco Coir Provider

When selecting a coco coir provider, learn how the product is harvested, prepared, and processed. The goal is to find a provider that adheres to the industry’s best practices regarding production. Pathogens are a concern, as the coir must sit for a period to dry. The producer will chemically sterilize the coir before it is put up for sale, but this process sometimes causes a break down of the coir’s fibrous tissues and must be done by experienced professionals.

A reputable coco coir provider works to avoid situations that could lead to pathogen growth. A dedicated system should be in place to control the aging process, and the coir needs to be rinsed and washed to remove excess salts. Finally, the product must be packaged and stored correctly so issues do not arise from the time the coir leaves the manufacturing plant to the time it ends up in the grower’s garden.

Obviously, the grow medium is only one aspect of growing cannabis. First, an area must be selected for this purpose, and this area must have room for all equipment, such as fans and grow lights. It needs to be clean and light proof.

When the grow medium has been chosen, it is time to begin selecting the equipment needed for the grow area. One thing to consider at this time is investing in equipment that can be automated to achieve the best climate for your grow room. Doing so makes your job as a marijuana seed grower easier. You have fewer things to monitor and may focus on improving your crop by trying different techniques. The basics can be handled by automation.

Next, select the grow medium and the containers to be used for the plants. A cannabis strain will need to be selected and the proper nutrients purchased. Finally, learn about the water that will be used to ensure that the plants have enough moisture. Cannabis is a very resilient plant, but growers in dry climates like Arizona will need to pay special attention to make sure the coco doesn’t get too dry for too long.

Certain growers have found they have issues using tap water for growing cannabis, especially for germinating their new feminized or autoflowering seeds. The cause of tap-water related issues may be related to the buildup of minerals, chemicals, and/or pathogens in the water that can disrupt pH, nutrient absorption, and more.

Start small while thinking big. Do not hesitate to experiment with grow mediums, lighting configurations, different strains, nutrient solutions and more. As you become more knowledgeable and experienced, changes will likely be made to the grow area and more. Do not give up. With time as well as trial and error, you will be growing amazing cannabis crops in no time, especially if you start with high-quality American seeds from weed-seeds.com!


Other Blog Posts 

Subscribe Now

And receive a coupon for 10% off on your first order. Signup for the latest marijuana seeds discounts, bogo's and other discounts for subscribers.