As with every other season autumn is considered by some as the best time to start composting. It is certainly a time that, because of the tidying and cleaning up of the garden in readiness for winter,
there should be plenty of material to compost and if undertaken early in the season the bin should have time get into its stride before the worst of the cold weather.
Autumn is also recommended as the best time to harvest
compost made by cold composting techniques and is also a good time to apply compost as a mulch. Compost and manure is usually dug into the plot during November or applied as a layer over raised beds. Compost can also be applied both to established beds and
around specimen plants. It can also be used as mulch to top dress the lawn in the autumn when people are less likely to spend time in the garden and may not worry that the lawn has taken on a brown appearance. If harvesting a plastic Dalek type bin, it is
easier to lift the bin off the compost than to try to remove the compost through the hatch provided.
Whether starting a new bin, or operating an existing one, getting it actively decomposing throughout the autumn, when the
weather is kind, will help to provide a good crop of compost in the spring. If an open pile or New Zealand bin is being used cover it, either with carpet, tarpaulin or a compost duvet, to prevent the material becoming water logged and aerate it to keep it
working for as long as possible.
There is likely to be a considerable amount of compostable material available in the autumn but much of it will be bulky such as pea or sweet pea vines. The volume can be reduced by
shredding. Shredding increases the surface area of waste to the microbes in the compost. If a shredder is not available, the waste can be spread on the lawn or a grass path and mowed using a rotary mower.
Mowing or shredding
is also advisable when dealing with herbaceous plants such as asters, delphiniums the stems of which would otherwise be slow to decompose. Even if the material added to the bin is not usually shredded during the rest of the year, it helps to do so with autumn
waste to speed decomposition of the material before the start of the cold weather.
If the compost heap starts overflowing either start a new bin or store the material until the heap subsides and the waste can be added.
The surplus material can be stored in a covered pile or buckets. It is important to keep the stored material dry, as dry material will heat up more quickly than wet. When added to the compost bin. Material being saved in the autumn for use as bulking
agent in food composting e.g. sawdust or composted wood chip should also be kept dry. (I keep mine in plastic dustbins)
There is likely to be a lot of material available at this time of year in addition to that already
In September crops of aubergines, courgettes, beans (French and runners), beetroot, carrots, chillies, cucumbers, peas, peppers, tomatoes, swiss chard and sweetcorn will be coming to an end and autumn crops such
as leeks, main crop potatoes and swedes will be ready to harvest. These should be trimmed on- site and tops and trimmings added to the compost bin rather than carried home as pulled or picked. Squashes and pumpkins plants will be available once the fruit has
matured and is harvested, Carved pumpkins can be composted after Halloween Composting Pumpkins
There will also be windfall plums,
apples and pears all of which can be composted.
Comfrey can be harvested until late September when it should be left uncut for the leaves to die off naturally.
In October, any remaining
summer crops can be composted along with potato helms and more beetroot tops as they are lifted. Any remaining climbing bean, pea or tomato plants can be shredded or chopped into small pieces for composting as the supports are taken down. Discoloured and blotchy
leaves are safe to compost as the organisms causing the blotches will be broken down during the composting process. The roots of plants with soil borne diseases such as brassicas with club-root and white rot in onions should not be cold composted as
the spores will survive.
The tops and trimmings of root vegetables will continue to be available for composting during November together with their peelings from the kitchen. Leaves, tops or finished plants such as
cauliflowers, the first Jerusalem artichokes, some oriental brassicas, turnips, autumn cabbages, celeriac, trench grown celery, leeks, plus final autumn lettuces, parsnips, swedes may also be available. A In addition there will be plants from the flower bed
as they catch the frost and when the plot is tidied for digging.
This is the main time of year for pruning fruit trees and bushes (except cherries and plums) proving more shredded material for the compost bin. If there is
electricity on the site a communal shredder might be a good investment. If there are a large number of trees on the site or hedges that need regular cutting hiring a larger machine or a contactor to shred the material might be possible.
Autumn annual weeds can be composted if the allotment is to be dug, manured and left to over winter. However, a keen composter will plan their allotment grow to provide a succession of crops both to eat and so that there is a supply of
material to compost over the winter using an insulated bin.
It is helpful to turn the compost bin, to mix the new material and aerate it, to encourage the composting processes before the onset of winter. Towards
the end of the month it is advisable to check the consistency and moisture level of the contents. If the material is too dry more greens can be added e.g. nettles and annual weeds along with water or the sludge from compost tea. If too wet crumpled cardboard
shredded paper, woodchip or sawdust can be added.
Wormeries should be moved into a shed or outbuilding or if they are to be left outside during the winter the bin should be insulated so that the contents and worms are not
frozen, I have found that a triple layer of bubble wrap makes an excellent insulating material which does not absorb water, is clean and easy to reuse. The worms will still need feeding during the winter, although at a reduced rate, so a removable
bubble wrap lid should be included. If the allotment is to be left to over winter it might be advisable to take the wormery home so that it is not neglected over the coming months. On the other hand, checking the wormery weekly is a good way of keeping
an eye on the plot over the winter months.
Bag autumn leaves for leafmould or as a carbon-rich winter source of Browns for the compost bin on the allotment where cardboard or shredded paper will not be readily available.
In the UK the usual advice is that autumn leaves should be treated separately to make leafmould rather than being added to the compost as they can be slow to decompose but in America they are often one of the main composting ingredients and a key source of
Browns during the winter. The autumn leaves can also be used immediately in the compost bin layering them with grass clippings, kitchen waste and other plant material but remember that the leaves tend to be slow to decompose, so this may not be
the method of choice (see Leafmould). Some leaves can be set aside to add to the compost bin during the winter months to provide a source of Browns when most of the other material being added is kitchen waste.