DIY Potting Mix for Cannabis Growers

Best DIY Potting Mix for Cannabis Plants – WeedSeedShop

Making your own potting mix can be a great way to advance your cannabis garden, or even a cheaper alternative for those growing weed for the first time. Whether you’ve grown before or it’s the first time, home making your own potting mix is the best way to ensure a high-quality soil.

At WeedSeedShop, we’ve delved intensively into how to choose your soil for optimum results from your garden. But the best way to get the conditions of your soil perfect is to of course, create your own. The advantages of making your own potting mix are that it is affordable, and this method gives you complete control over the balance of nutrients.

Making your own soil enables you to produce the highest quality weed possible out of your growing endeavour. This is not difficult and is entirely possible for those who have just started growing.

Why go down the road of DIY?

Choosing the right soil is imperative to growing quality ganja – it is where the whole thing begins! Even though there are quality potting mixes available in stores, the truth is that in fact, their quality varies not only from company to company, but also from batch to batch.

Creating your own potting mix means you can ensure the quality of your soil every time you grow. It is much cheaper to create your own soil, especially if you make your own compost and work with dirt from your garden. Conveniently, you can store your batch of potting mix and it will last much longer than products that you buy in stores.

In fact, doing it yourself is imperative if you want to grow your own cannabis organically. Often what you purchase in stores is chemically enhanced and doesn’t contain the natural biomicrobials that make your growing endeavour an adventure into permaculture.

Creating your own soil is highly encouraged, especially because your cannabis plant is something you should take care of from the very beginning. Fortune favours the brave, those who adventure into the world of DIY potting mix!

Creating the base

Best DIY Potting Mix for Cannabis Plants – WeedSeedShop

There are two ways to create the base of your potting mix. The first one is to buy your basic soil from a store. The second way is to create your own soil from scratch. We will go through both ways to create the base of your potting mix.

Making your own soil from scratch

To make your own soil, you are going to need to collect some ingredients. The point is that your soil should be full of “food-healthy” things that will promote soil that retains water and is also well aerated. Cannabis requires these qualities because root growth is imperative to a healthy plant. You also do not want it to contain nasty chemicals because these will eventually end up in your body.

The tools you will require:

  • A container to measure
  • A huge bucket to mix everything together
  • A water source (i.e. a hose or tap)
  • A fork
  • A separate container for soaking some of your ingredients
  • A sieve
  • A dust mask to protect against any particles (if you use organic materials this isn’t a huge deal, but still… safety first)
  • And all the ingredients that are about to be listed

The ingredients you’ll need:

  • 1 part Vermiculite

This material is a volcanic mineral that is used to retain moisture in the soil. It is sourced from many different parts of the world, and you can buy it online.

Vermiculite has been treated with heat in order to increase its water-holding capacity, and this is what is going to keep your soil very water absorbent. It also will retain some nutrients to make them available to your plants.

It does not rot or deteriorate at all, and basically stays exactly the same for the entire time it lives in your soil.

  • 1 part pre-soaked Coco Coir Peat

This material is a waste product that comes from the coconut industry, and it’s a very environmentally conscious way to add food to your soil. It is generally considered more ethical than choosing peat moss, which doesn’t renew and can cause problems for the environment.

  • 2 parts compost

You can buy great organic compost for relatively cheap, or for even cheaper you can make your own compost. Compost is a great source of plant food, as well as all of the healthy bacteria that keep your soil alive.  Your compost should be sieved before it is used in your potting mix.

  • ½ cup or 1 cup of Worm Castings (or humus)

If you have your own worm farm, you can add this humus to your mix. If not, you can buy worm castings. This also makes your soil better able to retain moisture and nutrients to be able to feed your plants.

It adds helpful angels in the form of microbes to your soil, is also a source of food and overall, this is a great addition to your homemade soil.

A part just refers to however much potting mix you want to make. Be consistent with your parts and you can create as much as you want.

How to make your own base soil

Best DIY Potting Mix for Cannabis Plants – WeedSeedShop
  1. Make sure you have sieved your compost and pre-soaked your coir peat in warm water. Use directions according to how much coir peat you’ve got. The directions should be on the product you’ve purchased.
  2. Mix the coir peat with the vermiculite in a bucket.
  3. Add your compost!
  4. Be a good grower, and check the pH of your soil! You’re aiming for somewhere between 5.8-6.5.

Now, you’ve just made a little, or a lot of your own home-made soil. Below, we explain which nutrients you should add to your soil to create the perfect environment for weed.

You can keep feeding the ecosystem that is happening in your soil by giving it compost tea. It is a great thing to give your plants while they are growing, and it keeps the soil in good condition, too so that you can reuse it in future grows.

The name for this recycling of soil is, appropriately, Recycled Organic Living Soil (ROLS). Through this process, you can maintain the living ecosystem of microbial life inside your soil so it is constantly regenerating itself, making it richer with nutritional information. To acquaint yourself with ROLS, you can read our article about it.

Buying base soil

The other way to create your base soil is to buy some good quality, organic soil. Well aerated soil that is easily penetrable is what you are looking for. Better quality soils usually contain ingredients such as peat moss (although as we’ve discussed, there are more ethical materials to use that are just as beneficial to cannabis), soybean, worm castings, compost, sand and oyster shell flower.

Make sure you check the list of ingredients in your soil. It should not contain any added nutrients. The problem with buying pre-mixed soils is that they are not made for cannabis, but for other regular house plants. The nutrients mixed into these will actually you’re your cannabis plants rather than help them.

Adding nutrients

Whether you’ve made your own base soil or you are buying the base soil, you will need to supplement your soil with nutrients. Worm castings really are the best organic material to add for nutrients, but you could also add blood meal, Epsom salts, rock phosphate, dolomite, bone meal, azomite and bloom bat guano. These promote the volumes of potassium, nitrogen and phosphate.

Now, it isn’t necessary to add all of these ingredients to your DIY soil. However, if you nail it from the very beginning, you provide your plants a nutrient-rich soil without having to add nutrients in the future.

The benefit of making your own potting mix rich with natural nutrients is that the nutrients can be provided at a constant and steady rate throughout the grow. Having to feed nutrients throughout the grow makes the nutrient availability staggered rather than constant. This is why adding the above ingredients is highly recommended.

Make sure that you distribute the nutrients evenly over the soil. It means you have to mix it all very well. Grind your nutrients into as fine a powder or mix, and try and mix everything together as well as you can.  It is important that they are evenly distributed in your potting mix so that you don’t end up with a batch of nutrient-rich soil and a batch of completely bare potting mix.

Now you are prepared with the best quality potting mix, homemade by yours truly. You know exactly what has gone into it, and in doing so you’ve created the perfect environment for your seeds to grow. Enjoy your home-made medium!


5 thoughts on “DIY Potting Mix for Cannabis Growers”

    1. Yes, because if the water pH is off, it will alter the pH of the soil, which can cause nutrient lockout.

  1. Once the soil is made , what should be used for nutrients ? Synthetic ok to start with 3 weeks into veg and onward while topping with worm castings ?

  2. Can perlite be substituted for vermiculite? Also, if I add the worm castings to the compost and vermiculite/perlite do I still need to add any of the other nutrients? I have them all, just confused about what to add and when!

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  • Author_profiles-WSS-Sera Jane Ghaly

    Sera Jane Ghaly

    I like to call myself the traveling gypsy wanderer of the world. Born in Melbourne Australia, but reborn just about everywhere else in the world. I have a healthy obsession with words and languages, using them as a vehicle to navigate this multi-dimensional human experience. My enthusiasm for marijuana started in the USA, and since then I’ve been traveling the world with the herb as my inspiration. Sweet Mary Jane has led me to shamanic ceremonies in the Amazon all the way to smoking ganja with the Babas in India.
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