Are you spending a fortune on bagged compost? For National Compost Week, composting expert Rod Weston provides a beginner’s guide to composting.
Why compost?
All allotment gardeners produce organic waste that can be composted, but many do not bother, preferring to burn it or take it to the council recycling plant and then buy shop compost! This not only damages your pocket, but adds to Co2 emissions and wastes a valuable free resources. Garden compost from the allotment is sustainable, it improves the fertility, structure and used as a mulch, water retention of the soil.
Bag your bin!
If you’ve taken on an allotment plot recently, you may have inherited one or more plastic ‘Dalek’ compost bins, or perhaps a wooden bin made from 3 or 4 pallets. If not and you want to try composting, ask fellow plot holders or check out social media as there are often free bins available.
When to start?
You can start composting at any time of year, but spring is a good time, as the lots of organic material will become available as you start weeding plot and harvesting.
Bin rotation and harvesting
The purist will say that a bin should be at least than 1 cubic m in size and should be turned regularly into a second and third bin. This is true if you want to make compost very quickly within a few weeks. However, many allotments opt for a more relaxed system – using several dalek bins, filling one, then moving on to the next and then harvesting the whole bin after about a year. Householders with small gardens can add material to their Dalek bins in relatively small amounts and harvest the finished compost though a hatch at the bottom of the bin in a continuous 12-18 monthly cycle.
Where to put your bin?
The location on the plot is not particularly important but leave space to harvest the contents easily. Ideally put the bins on soil and add a layer of twigs, woodchip of crumpled cardboard in the bottom of the bin .
Greens and browns
When composting you need to add roughly equal amounts of Greens (e.g. annual weeds and crop waste, fruit, grass clippings, nettles or comfrey and manure which are rich in nitrogen) and Browns (e.g. autumn leaves, dead stems, straw and wood chip which are rich in carbon), plus, torn-up or shredded paper and cardboard from home. One way of getting the Green: Brown ratio right is the add a 3-4 inch layer of Browns followed by a layer of Greens. These can be mixed with a fork or compost aerator at the end of the day with a layer of Browns being added on top of the material after mixing.
The materials will decompose more quickly if cut into short lengths or shredded. Long handled shears makes it easy to cut the material without getting backache. Grass clippings are best mixed with Browns - for example mix in woodchip together with the grass.
To turn or not to turn?
I would recommend turning the material in the top layers of the bin monthly for the first few months to let in air and avoid compaction. An alternative approach is to knock the bin over and then refill it. The third approach, followed by many composters, is to fill the bin and let it get on with it!
Whichever approach you adopt it will work better if the contents are kept moist. So water, with rainwater, periodically.
The lazy approach
Composting using the simple no turn method in a Dalek bin can take up to three years during which time you may have filled several bins but, by using this lazy approach, nearly all of the bin contents will be ready for use, meaning you can simply knock the bin over and fill a wheelbarrow with compost.
How to know when your compost is ready
The finished compost will be crumbly, with a soil-like texture and pleasant ‘woodland’ smell. It is then ready to use - the majority of your allotment compost can be used as a valuable 5cm layer of mulch added to the soil surface – boosting soil fertility and moisture retention for your crops.
Want to progress?
After you have successfully made a few batches of compost in Daleks and experienced the benefits of home/allotment made compost, you could then graduate to a larger sectional plastic, tumbler or even pallet bins which can be used to ‘hot compost’ waste. This is a much quicker method of composting, but requires a little more time and effort.
Rod Weston is an organic master compost expert, who operates a composting demonstration site with over 30 composting bins, wormeries and cooked food composters at Stokes Wood Allotments in Leicester. He runs our NAS composting Facebook group and is also author of ‘A Gardeners Guide to Composting Techniques’ published by Crowood Press.
