by Alex Robles
Hello my beautiful fellow cultivators, I hope everyone’s gardens are looking good. Today I’m going to talk about choosing the right premixed, bagged, potting soil for your cannabis garden. Now this can be confusing with all the different types of potting soil mixes that are out there. Here are the things I look for when I’m shopping for a bag of soil.
First of all, I stay away from any mix that has time release fertilizer pellets like Miracle-Gro. I have less control when it comes to feeding my plants nutrients and run the risk of seriously burning my plants with those pellets. Just keep this in mind when you’re feeding your plants nutrients while running this type of soil. I understand if you live in a prohibition state or a small town that your choices are limited, so I’ll put a more detailed post up about this type of soil and how to grow with it later.
Before I look at anything else I check to see what the nitrogen (N), phosphate (P), and potassium (K) ration is, it should be clearly marked on the bag as NPK. These are the macro-nutrients (major nutrients) that your marijuana plant will use. I make sure that the ratios are even (i.e. 10-10-10 or 20-20-20). Since I’m going to be using this soil in every stage of my cannabis garden, I like a 10-10-10 mix because it’s not too high or hot and I don’t have to worry about burning or killing young seedlings and clones.
The bulk of most premixed soil will be a mixture known as loam which is mostly made up of sand, silt, and clay. Perlite or vermiculite are the little white pebbles that have no nutritional value. They are added to the mix to help the soil hold water and helps air move around the roots system.
Now, what I really pay attention to are the amendment or extras that a bagged soil mix will have. I like my soil to either have a seabird or bat guano. I prefer a seabird because it is a more sustainable type of guano (poop). Guano is a good source of nitrogen, potassium and phosphate which are the essential macro-nutrients that your cannabis plant needs.
The next thing I look for is earthworm casting (poop) because it is a great organic fertilizer. Aside from being nitrogen rich it also helps the soil stay moist ( water retention ). The amazing thing that I love about good quality worm castings is that it helps the plant produce chitinase ( kite-an-ase ) in its sap. Chitin helps make up the exoskeletons of arthropods which is what most bugs are that can infest your cannabis. Chitinase breaks down chitin, so when a pest nibbles on the plant it gets a spicy dose of chitinase and decides to move on.
Another thing that I like my soil to have is humic acid because it helps plants digest trace minerals like magnesium (Mg), calcium (Ca), and iron (Fe). It stimulates microbial activity which in turn helps plants take up nutrients at the root zone.
I also like to see a little sphagnum peat moss because it helps with water and nutrient retention for plants grown in containers. The problems with peat moss is that after a few growing cycles it starts to compact and it turns more acidic as it breaks down. There’s also a sustainability issue because peat moss is mined.
A crab meal or fish meal is another extra I like to see because it’s a great source of nitrogen for plants. Last but not least I check to see if the soil has some beneficial soil bacteria like bacillus that will help the nutrients become available to the plants.
Right now the mix that I’m running is called Recipe 420 from E.B. Stone and it has all these amendments plus a few more. The soil will feed my plants for at least 8 weeks, after that the nutrients in it could get depleted. I need to think about adding soil amendments when that time comes, to keep my garden at an optimum level.
Well, that’s all the advice I have to give on premixed, bagged, potting soil. Remember that we learn how to grow so we can help others learn how to grow.
Grow, Learn, Teach