There’s a wormery for everyone, whether you have a garden or not

With a wormery, everyone can transform their food waste into a rich compost that will help produce healthy, lush plants. Sue Fisher tested nine to reveal our best buys

Whether you have a balcony, garden or even no outside space at all, there’s no need to let your waste go to waste. Anyone, anywhere, can turn household food waste into rich compost that can be used to grow healthy plants and crops. Compost produced by worms is more fertile than garden compost. A little goes a long way and it can be used for planting, mulching, top dressing and in potting compost.

In a range of sizes and designs, wormeries can suit all households and locations. Neat and compact, they process waste quickly once established, indoors or outside. Wormeries are vermin-proof too, so cooked food can be safely composted. They also allow you to see worms in action, and are ideal for anyone who wants to be a greener gardener.

Most wormeries are a tiered or stacking design, but there are also single-chamber units. As there are several buying options, the price listed covers what you need to get started: a base with a minimum of two trays and a starter kit including worms or a worm voucher.

How we tested

Our wormeries were set up last summer and assessed over the rest of the year. Every part of the process was considered, and worms were given cooked and raw kitchen waste, paper and brown cardboard. We used the following criteria, with equal marks attributed to each:

■ Design & setup. Instructions’ ease and clarity, siting conditions and extra features.

■ Ease of use. The simplicity of adding waste and harvesting liquid, design problems, and features or accessories that affect use.

■ Compost quality & harvesting. The quantity and quality of the compost and liquid, and whether the worms were thriving.

■ Value for money. As well as all of the above we considered quality and durability, RRP, warranty and eco-credentials.

Single-chamber wormeries

Large, single-chamber wormeries process all the waste in one bin so the waste is added to the top. Compost is then simply harvested from below or needs emptying to access the finished compost.

The worms

Wormeries contain composting worms such as brandlings – also known as red, manure or tiger worms – that live in decaying, organic matter, and have huge appetites and a fast metabolism. Earthworms, which are bigger, live in soil and aren’t suitable.

Top tray This is where fresh waste is added. Cover with a coir mat or moistened brown cardboard/crumpled paper to reduce flies and help with insulation. Bottom tray This contains the finished compost. Remove and set aside upper trays to harvest it. Once emptied, this can then become the top tray. Tap or drain outlet Sited on the side or beneath. If on the side, the wormery may need tilting to drain completely. Underneath is most efficient, but less accessible. Lid Keeps out rain and flies. Base or legs These raise the wormery off the ground for drainage and ease of use. Stacking trays These contain worms and waste, added initially to one tray. When full, tray two goes on top and the worms work up through its mesh base. This can be repeated with a third and even a fourth tray, depending on how much waste you produce. Sump This holds the liquid that is produced and needs draining every few days: dilute 1:10 with water, and give to plants or add to garden compost bins. Some worms will fall through, so the sump design is important, or they can drown. Some models have a drain tray instead.