One of the best ways gardeners can break down organic matter is to use composting worms to convert food scraps into nutrient-rich, pH neutral worm castings, which produce a high quality soil conditioner. A convenient container in which to do this is an old bathtub, but almost any sturdy, waterproof container can be used. Worms are the most willing workers that can be found in the garden. Composting worms are a different type to the deep-burrowing earthworms that aerate the soil. Composting worms are surface dwellers that thrive in the leaf litter layers in moist regions around the world. To increase numbers, ideal conditions have to be created. There are three common types of composting worms; Tiger worms, Indian Blues and Red Wrigglers. They can be difficult to tell apart, but all live quite happily together and all require similar conditions - cool, moist, dark, oxygen-rich environments with a regular supply of food.

While there are ready-made worm farms available, it is easy to make your own. Two bathtubs will accommodate the food scraps of an average family of four. One side of the bath is filled with food scraps and the worms are introduced. When this has nearly been consumed, the other side can begin to be filled and the worms will move to this side, leaving the original half filled with worm castings ready for the garden.

There are some simple steps to make your own worm farm in a bathtub.  Slits need to be cut with an angle grinder, into the bathtub about 5 cm from the base. These will provide aeration to the worm bed.  Use a silicone sealant to attach a mesh screen over the drain hole to reduce the chance of it blocking up. A plastic colander could be used.  Fill above the incisions with coarse gravel for good drainage then lay down a layer of weed mat or tight shade cloth to prevent the worm castings from mixing with the gravel.  A mixture of coir fibre and straw that has been soaked in water should be introduced to one side of the container first. When the worms are introduced and food is available, the conditions are conducive to them breeding.  Add some aged horse manure.  Now it is time to add the worms, which are available from garden centers or worm farmers.  Cover the worms with a piece of carpet that has been soaked in water, and drained. This will keep the worm farm cool and moist. (If the worm farm ever seems dry, re-moisten the carpet. Never drown them with a hose). Worm farms need a shady, undercover position where they won’t be drenched by rain or irrigation.

Don’t overfeed the worms or the food scraps will just rot. Worms will breed up quickly if the conditions are right, and ideally will double every three months. As they increase in number the amount of food scraps can be increased proportionately - up to a kilo of food scraps per square meter per day. The smaller the pieces the quicker it will be broken down. Don’t use citrus or onions as worms dislike these. These can go into the compost bin. Meat and dairy foods should also not be used as they attract flies, rats and wasps as they rot. Think about burying these under a favorite fruit tree.

When the worm farm is operating successfully and you notice pests like mites, vinegar flies, maggots or slugs just dust the top with lime. Check to make sure you haven’t added too much food.When you notice that the worms have left the first side, the castings are ready to use on the garden. A handful can be used in planting holes ensuring that the roots of plants have a wide range of nutrients and moisture available to them. Liquid worm castings also make an excellent fertilizer. A generous handful in a 9 liter bucket of water stirred vigorously can be watered onto plants weekly during the growing season will produce outstanding results. A wonderful advantage is that this mixture will not burn plants.

Excessive applications are wasteful. Soil has a limit to the amount of nutrient-laden moisture it can hold at a time; so small regular applications are best.

Trackback URI | Comments RSS