Numbered from '0' to '10',
10. A lid
9. Insulation / Warmth
8. Moisture Mat
7. Worm bedding
6. The food waste
5. 'Browns' / Worm bedding, such as Leaf Litter...
5 a, Grit from Soil...
5 a, Grit from Soil...
4. Worms and bedding or vermicompost
3. 'Browns' / Worm bedding
2. Drainage
1. The container
0. Liquid collection
-1. In the Cool….shade
10. A lid
This can be thick to insulate the wormery. It needs to be a good fit, to keep out rats, and reduce the flies’ access to the waste. If weighted down with e.g. a brick, it is more secure.
9. Insulation / Warmth
Insulating layers that trap air, such as an old blanket keep warmth in, when temperatures drop in the winter.
A small wormery can be moved inside or under a shelter. The worms’ optimal temperature range is 5 – 15 º C. They slow down a lot and cannot cope with so much waste when they cool down.
8. Moisture Mat
A piece of thick polythene or tarpaulin on the top of the waste keeps moisture in. The worms need this in order keep their skin wet with mucus so that oxygen dissolves and enters the body. Their skin is a lung! We are not so different. After all we evolved from worms, or something like them, and the bit of our skin that we breath through is kept moist by being inverted inside our bodies; it is our lungs.
7. Worm bedding
Leaf mould or damp torn up cardboard, or damp shredded paper. This is kept as a layer over the food, in which the worms can easily move about, escape bad areas, and get to good areas. One American method suggests pulling this layer aside to place waste under it.
6. The food waste
Once the wormery is established start adding small amounts of food, and monitor how it is being eaten. If it is smelling OK and breaking down, you can add bigger quantities. I recommend no more than a layer of 1 – 2 inches at a time, once a week. Turn this top layer of new material gently, to help aeration, and to monitor how well it is rotting.
In theory all food can be composted in this way. Raw well chopped vegetable waste is the easiest. (large lumps such as whole potatoes need to chopped down to 1 inch diameter).
Small amounts of dairy, meat or fish are also OK, if mixed in and buried in the other waste, thus reducing fly access and smell problems.
If there are rats, then the wormery needs to be rat proof…! There must not (by law) be farm animals on the same premises. Diseases can be spread to them especially if they can get in and eat it. Feeding chickens raw veg scraps is OK.
5. 'Browns' / Worm bedding, such as Leaf Litter...
Leaves are good worm ‘bedding’, providing them with a reliable habitat in
which to retreat. It also adds carbon to the mix, so giving energy to
microbes, and fibrous structure. You can add it fresh or well rotted.This provides ‘structure’, and enables air to move through the compost. This enables the beneficial ‘aerobic decomposition’ to take place.
This is much quicker than decomposition without air (anaerobic), which smells bad, and releases methane.
5a . Grit from Soil
Worms need some grit, to break up food, in their gizzard.
They do not have teeth, so after swallowing the soft rotting matter, this grit helps them to break it down further.
Therefore some soil needs to be added: a couple of handfuls every few weeks.
4. Worms and bedding or vermicompost
The worm species used for composting are usually:
The Tiger worm (Eisenia Fetida)
Or its close relative, Eisenia venata
Worms are added in what is called ‘safe bedding’. That is a well rotted material they are happy to be in, such as the compost that they make themselves (known as vermi-compost), and/or well rotted leaf mould or similar.
3, 5. 'Browns' / Worm bedding
To balance the wet food waste which is termed ‘green’, a source of carbon is needed. This is called ‘brown’; such as torn cardboard / card, shredded paper, straw, leaf litter, pet sawdust, wood chips….etc. There needs to be at least as much browns as greens (by weight).
2. Drainage
Fluid and too much dampness can collect in the container so it must be able to drain away. This is important, to stop water-logging.
Water logging leads to anaerobic conditions (without air), because the material compacts and stops air flow. This results in a putrid, smelly, slow rotting process, in which worms die.
Combinations of the following are used to allow drainage:
- Stones or chippings, with matting above (to keep them separate from compost)
- A raised floor with holes in, which allows fluid to collect in a lower chamber or sump (but this must in turn be drained regularly or continuously, e.g. by a tap which is left open, and drips into a bucket)
- Holes in the base of the container
- A Tap
The fluid or ‘leachate’ may be collected as plant food. If it smells bad however, it must be further broken down, by pouring it back into the wormery or another composter. Worm ‘tea’ is a more reliable plant feed.
1. The container
Should be at least 2 foot square, and can be 1 – 4 feet high; made of wood (good as it beathes), plastic, metal, old bath, barrels, dustbins, etc. It needs air holes in the sides to allow aeration, and holes at the base to allow drainage.
0. Liquid collection.
Sometimes,
a liquid will drain out. If it smells OK, it is good plant fertiliser.
If it smells bad, then it needs to aerobically decompose some more, so
pour it back into the wormery.
-1. In the Cool….shade
Keeping cool in the summer is important as the worms’ optimal temperature range is 5 – 15 º C. They die if they get too hot. So the wormery needs to be in the shade. This is the opposite of a ‘normal’ composter in which heat is welcomed. So, a dalek type composter would be sited in the full sun. It is a good idea to have a couple of composters, one of each sort. The hot one will compost more of the garden waste, and excess food waste that the wormery may not always cope with (e.g. in the winter). Also, (for the keeners ! ) having two wormeries next to each other is useful in allowing alternation if one of them is not coping.
