Over the last few years we’ve been hearing great things about vermicast (i.e. worm manure). And when farmers are talking up one kind of shit over all the other types of shit they have access to, we’ll it’s time to listen up — cause farmers know their shit.
What makes worm castings so special — while they are kinda like meta-composting. While most farm animals eat plants and produce manure, worms eat manure and produce…umm… super manure; likewise while composting breaks down plant material, worms eat the compost and break it down further which provides a host of additional perks.
Ultimately when these worm castings are applied to the soil, either directly during seeding or as an eco-tea extract, there are a number of benefits. Worm castings have been shown to aid in the creation of a more resilient and robust soil microbiology, and help plants better cope with environment stresses. As well as increase plants’ early season vigor and germination rates as well as plant biomass and yield.
Worm castings are an extra additive and do not replace any other regime. Unlike many other soil additives, worm castings benefit the soil more by stimulating biology (i.e. microbial life) than through the addition of any particular nutrient or mineral.
And best of all, building a vermicompost system is easy and pretty much free. Not completely, you will have to spend a couple bucks on worms, but apart from the actual critters, most everything else should be scavengable on most farms.
While there are a few different methods of vermicomposting available, which one is best suited to your farm will likely be dictated by climate. Warmer environments can get by using the windrow method where the composting can be done outside, on the ground. However, cooler environments, like most all of Canada, will need to use an indoor method for year-long usage.
At Prairie Son Acres, we opted for what is known as a ‘flow-through’ or ‘raised-bed’ design for our vermicomposting system.
In this system, new material (i.e. worm food) is added to the top of the elevated worm bed as old material (i.e. worm castings) is drawn from the bottom. As the worms are attracted to the new food at the top of the worm bed, the worms will always be moving upward which works to automatically separate the critters from the castings which collect at the bottom.
Our homemade system was constructed from re-used farm materials. Most notably the tank which contains the worm bed was formed from a repurposed 1000L plastic tote and cage with a false bottom made by laying rebar approximately 2-3” apart.
The plastic tote was cut once to remove the top and again to remove the base. The middle section was refitted around 12 inches over the base using a homemade rebar frame which reinforces the bottom of the metal cage. When it is time to harvest, the worm castings are cut from the bottom of the bin using a rake pitch fork or whatever you have that is handy, even your fingers will do the trick. The metal cage is cut away from one side of the base allowing the bottom piece to slide out like a tray once the castings have been harvested.
We purchased 10 lbs of worms (i.e. red wriggles), once the tank was complete. We put about a foot of our homemade feedstock into the tank; mixed in some extra shredded paper, and dumped in our worms and let nature do her thing.
This is a simple and very low maintenance design.
Once the tank was constructed and stocked with worms the castings were ready to be collected after roughly four months with new feedstock being added every 7-20 days. Click the link to get our recipe for worm feedstock.
One crucial bit of advance is to be sure not to overfeed the worms. The worms will always move upwards towards new material, if new material is added before the previous batch has been fully consumed then worms will move to the new food before the first batch has been fully converted to castings. It is far better to underfeed than over feed.
Once the castings have been collected they can be bagged and stored in a cool dry place until they are needed.
Also, just like when handling any other dried, powdery material, masks are recommended when handling the dried worm castings.