I have mentioned the use of worm castings in several articles, but have failed to describe why it is important to use. This is probably the most used amendment on my shelf and it can literally be used at any time, and almost any way, with great results. As the title suggests, there is some magic to it. That magic comes from the huge volume of beneficial microbes that are native to worm castings. How those microbes work is poorly understood, thus it is magic!
“Casting” is another fancy way of saying excrement, feces, or poop. When earth worms have fully consumed their food you are left with pure worm castings. The mixture of microbes in the gut of the worm have an excellent balance of beneficial microbes that are transferred directly into the castings. These microbes are decomposers who create nutrients that can be taken up by our cannabis plants.
The microbial content of worm castings along with the nutritional content are perfect for custom blended organic living soils such as the blend I use. This is a critical element in a new soil mix as it provides the microbes needed to break down the solid amendments added to the soil. In addition to the nutrients and microbes, castings also contain enzymes that can assist in breaking down nutrients into plant usable forms, along with humic acid. All of these things are invaluable in your soil.
Top dressing with castings is an excellent approach, particularly if you, at least partially, water from above. As water moves through the castings is carries nutrients and a fresh army of microbes into the lower layers of soil. Over time, this top dressing seems to ‘melt’ into the soil and eventually disappears. I like to top dress with small quantities of solid amendments along with worm castings that start decomposition of those amendments immediately.
Worm Tea is another great way to use castings. There are many different ways to accomplish this, but at the end of the day you have a dark colored, enriched water. Similar to top dressing, this water is now full of nearly all the components needed to make your plants healthy and happy.
In my opinion, worm castings are superior to compost for use in custom soil mixes. Compost can come with a huge variety regarding the inputs used to create them. Composts are more likely to come with larger debris (sticks and so forth) that are not beneficial in the soil. Compost is also far more likely to carry pests with it.
Quality worm castings should have almost no smell, still be moist to the touch, and be comprised of small, consistent football shaped nuggets. If castings are smelly or dried out, you should try a different brand. Some castings may still contain small yellow-brown sphere’s that are earthworm cocoons. For this reason, I also recommend using red wiggler earthworm castings. Red wigglers are known to moderate their population depending on container size and available food so you shouldn’t have any issues with over-population should those cocoons hatch.
Happy Harvests!
— The Lit Farmer —