Composting and Worm Composting – Often Confused!

An introduction to composting and worm composting

Having acquired an ordinary compost bin from either a retailer or the local council many people believe that by adding worms it becomes a wormery, this is not the case, they are two different systems, read on to find out why!

First some information on the two different systems.

“Ordinary” composting bins or heaps

This method relies on the microbes and air present to break down the waste, if heat is being generated the composting is working well and the waste will reduce into good compost.                                                                                              Because it is warm or even hot it is not a good idea to add worms believing they will help, the heat will kill or drive the worms away. For composting to work well, like all living things the microbes in the compost need a good balanced diet, this is a mix of green waste (kitchen scraps, a little cut grass etc) and brown waste (dead leaves, paper, cardboard etc) with a good supply of air, this mix should be about half and half, mixing this all together allows air into the waste, regular stirring up introduces more air and allows the compost to continue working, hence the reason for “turning the compost heap over”.

So what can go wrong?

Compost bins usually fail because they are not regularly turned over, they then become stagnant and can even smell, this is not good compost, the compost bin should be started again and the old contents spread on the garden and dug in at a later date.

“Wormery” composting or vermicomposting

As its name suggests this is done in a wormery and is distinctly different from ordinary compost bins despite much of the information available and most of this comes from retailers of such bins!
Worms work on surface area and not depth of bin so in most cases, anything over about 2 feet deep is wasted space and in fact, if used can create the “anaerobic” conditions talked about above. One of the most important factors that affects composting worms, their survival and success is the availability of air within their working environment, therefore the wormery must provide this in the form of good ventilation, the tall, upright plastic bins do not provide this. Once a suitable wormery is acquired, the worms must be installed in a bedding material, this is distinct from the food materials (waste) that is added after.
The bedding material is the area that the worms live in at the start, if conditions in the wormery are a bit off, they will seek refuge in this safe area, it is also treated as food which is why it is usually slow for the worms to process the new food you have given them, after all, they are surrounded by food!
Bedding can be made up of a variety of materials, a mix is best, some more commonly used materials are damp paper/cardboard, well rotted garden compost, well rotted manures, leaf mould, Moss peat, although there are ethical questions in using this and the moss you rake out of the lawn, do not use bagged potting composts from the local garden centre. The bedding in any wormery needs to be at least 8 inches deep up to about a foot.
Once the worms and bedding are installed, feed the first food layer, cover half the surface area to a depth of about a couple of inches, next cover this directly with a piece of black plastic even if the wormery has a lid. After about a week, check and see if the worms are feeding on the food layer, if they are nicely active feed the same amount again, if they are not active DO NOT feed, most problems are caused by continually adding food, creating anaerobic conditions and killing off the worms. Slowly build up the levels of feed according to the activity of the worms, what you see is far better than what you have read. You should now have a healthy, active wormery.

So, what can go wrong?

Number one problem has to be overloading with waste food, creating the anaerobic conditions above.
If the worms have insufficient air in the system they will do their best for as long as they can but then as the conditions become intolerable they will leave the bin (some bin manufacturers have overcome this problem by sealing and clamping the lid!) worms have a really good mechanism for crawling up the smoothest of plastics and this is why you find them all over the inside of the lid in their desperation to escape, if they cannot leave they will die. If you have one of these bins and wish to start again, it must be drilled full of holes – as many as you can without it collapsing and no the worms will not leave through the holes UNLESS the conditions inside have gone wrong, give them good conditions and they have no reason to leave.

Some waste foods are not suitable and even harmful to worms, raw citrus fruit skin, raw onions and members of the onion family such as garlic, all fermenting products and this includes warm damp bread in large quantities, some less obvious things such as using fly spray in the bin or any other chemicals.

Migrating worms

You have set up the wormery exactly as advised and yet the worms are crawling up the sides and out of the lid, why? Worms can be unsettled by many things, a constant vibration (nearby air conditioner) unsettled weather particularly low pressure, rain and storm conditions or the most common reason – they just do not like the bedding you have given them, if this is the case and you find the worms are wandering then leave the bin with the lid open under a low level light at night, just for 2 or 3 nights this forces them to stay and then they should settle, its also a good idea to place a wet cloth under the bin whilst doing this to catch any stragglers.
At Worms Direct we supply a worm and bedding kit, the bedding has been actively used by the worms and is home from home and they will settle much quicker.

I hope this has been useful, please feel free to copy and download for your own private use. Strictly no commercial use or reproduction without our express, written permission.

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