Anyone growing autoflowering cannabis plants in soil has probably heard of different fertilizers that you can use to amend the soil.
Worm castings are a popular choice as a fertilizer because they are loaded with beneficial microbes that will help break down compounds into readily available nutrients for your plants.
Worms are an often underappreciated contributor to strong plant health as their digestive process is responsible for nutrient availability and pest management in plant growth. This is why they are used in an amendment to revitalize the nutrient density of soil.
What are worm castings? Is it good for growing cannabis?
Worm castings are the result of a digestive process, as the worms eat organic matter, they convert it into microbes, nematodes, and various other beneficial elements that enhance your soil’s vitality.
Worm castings can also be called vermiculture or vermicompost as they can be used in a variety of formats.
In terms of cannabis growing, worms also break down ammonia in your soil to create nitrates which is the easiest form of nitrogen that your plants can absorb. Since this is one of the essential macronutrients your cannabis plants require you can start to see how worm castings can benefit your plant.
Using worm castings for your autoflowering cannabis can also help out the root system. Since certain diseases can be prevalent in the root area as it is constantly wet, worm castings can help strengthen the natural microbiome that lives down there, providing an effective barrier against things like pythium and septoria.
Worm castings aren’t all the same and should be researched before use. For example, worms are excellent at absorbing toxins in the soil and as such, can transmit that toxicity into the soil which eventually works its way into the plant and our bodies when consumed.
DDT is a pesticide that is now banned across much of the world, however, it is one toxin that earthworms can pass into the soil once digested.
Can you grow autoflowers directly in worm castings?
Using worm castings as a soil amendment is the most common way that it’s used because it provides a large amount of nitrogen. However, if you were to use worm castings as the growing medium you might see a different effect. Your plant will more than likely start seeing nitrogen toxicity if you use too much.
Worm castings act as a slow-release formula as they guide the soil microbiome to make the most of the available nutrients.
Even though they provide a low amount of the actual nutrition, it would take a lot to cause adverse effects, but it has been known to happen.
Remember, with cannabis, too much of anything is never a good thing.
How to use worm castings on your autoflowers?
While some growers use worm castings as their growing medium, it’s best used as a fertilizer instead. Up to a quarter of your growing medium (by volume) can be worm castings with other fertilizers providing the bulk of the micronutrients needed. Simply use it as a top dressing or mix it in with your growing medium before transplanting.
Some growers believe that worm castings should be used alongside a normal nutrient regiment as their bacterial effects far outweigh the nutrient capacity.
How to make your own worm castings?
Worm castings can be expensive if you’re using a lot of them; however, with a little time and patience, you can make your own soil amendments for your autos.
You need a large plastic container and a lot of earthworms, upwards of a thousand of them, to be specific. Fill the container with materials like sawdust, coco coir, and even shredded newspapers. In fact, you can add everything from your kitchen compost, coffee ground, eggshells, and old bread. All of this will get digested by the earthworms in the plastic container.
Leave it outside for a couple of months and you’ll start to see the transformation as the worms will eat through everything and leave their castings for you to use in your garden.
Afterward, you can take the worms out and put them in another container to keep, just be sure to keep feeding them so they can survive. This is by far the cheapest way to get a large amount of worm castings and the quality will be top-notch because you controlled what the worms were being fed.
If you’re really confident in your cannabis plant’s health you can even add the worms directly to your soil. Since the worms will only eat dead matter your living cannabis plant won’t be damaged.
How often do you need to use worm castings?
Adding worm castings to your soil can be done once or twice during the grow cycle or it can be added every few weeks, it depends on how you take care of your soil.
Most growers will load up their growing medium at the beginning of the growing cycle to make sure there is ample nutrition available to their plants as they start their life in the vegetative state. This way you can just add a top dressing when your plants start flowering or if you notice they need some extra nitrogen.
If you’re using a simple soil approach then you’ll need to apply worm castings more frequently throughout the grow cycle as the soil will become depleted more frequently.
Worms castings are an awesome addition to any nutrient program for your autoflowering cannabis plants.
They provide accessibility to nutrition, and soil rebalancing in regards to PH while being a potent defense against the likes of molds and pathogens that could affect your plant’s root system.
If you are feeling adventurous and need to offload some kitchen scraps, creating your own worm castings is the best way to ensure that there are no lingering toxins or heavy metals that could be transferred over to your plant. Regardless, your autoflower harvest will thank you for adding this nutritious amendment.