Worms are definitely on the side of the permaculturist when it comes to benefit to the garden. They are one of the most effective methods of conditioning the soil. Worms break up the soil structure, allowing it to become aerated and allowing moisture to percolate down into it. This “loosening” of the soil also enables plant roots to penetrate deeper into the soil, bringing nutrients up towards the surface.
Worms also break down organic matter, releasing nutrients into the soil from where they can be used by plants. As they eat their way through organic matter, they produce castings, which are a natural nutrient-rich form of compost, that is an ideal addition to your garden beds.
Instituting a worm farm on your permaculture plot ensures a consistent supply of castings, helping your soil stay in top condition year round. Creating a worm farm, in which the animals breed, mature and process material is easy and can be done in just a few steps.
You need a container that can drain to keep your worm farm in. While there are specially made worm farm containers on the market, you can just as easily use recycled materials – which is better for the environment and your pocket. A series of stackable containers, such as old wooden boxes, used plastic crates or Styrofoam containers are ideal – with the worms living in the top containers, and the bottom serving as a repository for drainage – but some enterprising gardeners also use old bathtubs. Whatever you choose for your container it needs to be watertight and able to protect your worms from extremes of heat of cold. Poke some holes in the top container and cover with shade cloth so that the worms don’t fall through them.
Site Your Farm
Decide where you will put your worm farm on your plot. For the worms it needs to be in a position that does not get too hot or too cold, particularly avoiding locations that are prone to frost. Under a shady deciduous tree would be ideal, as the tree losing its leaves in the winter allows sunshine to reach and warm the farm. You will also want to place your farm somewhere so that it is energy efficient for you to remove the worm castings and place on your beds. Look at a central position in zone 1 of your plot.
The worms in your farm need material in which to live. Typically, it will include some shredded newspaper mixed with some compost and a little garden soil. Other options include mushroom compost, grass clippings and coconut fibers. You want to provide a good depth of material for the worms to live in, so half fill your top container. Water the bedding material so that it is just moist.
Unfortunately, you can’t simply take earthworms from the garden and put them in the worm farm – leave them in the soil to help improve the structure. You need species for your farm that are adept at composting. You should be able to source from an organic supplier, either locally or online. There are several species from which to choose. Tiger worms are one option, while Red Wrigglers are another. If you are in a warm climate, Indian Blues are a good choice, as they do not cope well with the cold.
The worms in your farm will eat a wide variety of organic matter. Indeed, they will eat most of the things that would typically go into a compost pile. So you can feed the worms fruit and vegetables scraps, shredded newspaper, old mulch, coffee grinds, leaf litter and garden prunings. Dried eggshells make a good addition as the calcium they contain prompts the worms to lay more eggs.
It is a good idea to add another layer of shade cloth or a few sheets of damp newspaper over the top of your worm bedding, once the creatures and food have been added. This helps prevent vinegar flies and maggots getting to the worms. Place the lid on your top container to protect the worms from the elements.
To keep your worm farm functioning efficiently, you need to ensure that the bedding remains moist and the worms have enough fresh food. You will need to let the worm population guide you as to how much organic matter to add. If you find that some food is staying around and going moldy, you are giving them too much. However, generally, worm populations will respond to available food supplies and breed accordingly. It is also a good idea to add a handful of garden soil to the farm every so often, as the sand and grit in the soil helps the worms grind up their food.
As you worms multiply and the castings they create build up, you can migrate them up into the top container of your worm farm so you can harvest the castings. When the middle container is almost full of castings, place some bedding in the top container (having remembered to create drainage holes and covering them with shade cloth). The worms will migrate up to the new bedding. When they have migrated you can simply remove the middle box, harvest the castings and use this container to migrate the worms again when needed.
Use the Drained Liquid
The bottom container will collect liquid that drains from the worm farm. This is waste from the worms but it is not useless. Dilute the liquid with water until it is the colour of weak tea and then use as a liquid compost on your garden beds. Keep a check on the level of the liquid in the bottom container, as you don’t want it to get so high that it seeps back into the worm’s bedding.
Use the Castings
The castings act as a great slow-release compost for your garden beds and potted plants. Adding them to the soil will also prompt microorganisms already there to become more active and process the castings into the soil, making their nutrients available to your plants.