Most gardeners use lots of compost, to improve the structure of soil and to add nutrients, as well as for mulch to keep soil moist and to suppress weeds. It’s particularly useful in Dulwich with its clay subsoil. I use a lot and make most of my own.
How do you make the stuff?
You need a mix of green vegetation (e.g. grass cuttings, vegetable waste, weeds - but mind those seed heads) and woody brown material (e.g. straw, dead leaves, prunings, woodchips, scrunched-up newspaper or even cardboard), best placed as layers in a compost bin. Add water if needed to keep the heap moist, and turn it periodically to mix and aerate the ingredients (so two or more bins are best, moving the contents to the next bin when full - it gets easier as you move the heap along!). I have a shredder for prunings etc. I sieve the output using a wide-mesh sieve, adding any left overs to the start of the next batch. The cycle takes three to six months. Dulwich Riding Stables is a good source of often free stable manure with a straw or woodchip base.
Where can you get compost bins?
Compost bins help retain warmth and moisture. Southwark Council subsidises a range of compost bins and wormeries, with a 330 litre black plastic compost bin available for £10 from the marvellous Reuse and Recycling Centre off the Old Kent Road, or two for £15. Providers of wooden compost systems include archwoodgreenhouses.co.uk, tate-fencing.co.uk and originalorganics.co.uk.
Or you can make your own, the larger the better. The Which? Gardening factsheet How to make a compost bin shows the wide range of materials that can be used, from chicken wire to wood, with the key ingredients being ventilation gaps in the sides, a removable front or side for easy access, and a cover (old carpet) or lid to keep out the rain and keep in the heat. The cheapest bin? - four pallets, free on most Dulwich building sites.
What does the Council do with your garden waste?
The contents of those brown bins are composted by Veolia, and sold as an organic peat free soil conditioner for agricultural, landscaping and garden use under the Pro-Grow brand. It’s available at the Old Kent Road depot at £10 for four 30-litre bags. So, you can make your own compost or you can buy it back.
The RHS website is a good standby, and the Dulwich Vegetable Garden at Rosebery Lodge (open throughout the year on Wednesday and Sunday, 10.30am to 12.30pm, Sundays only in November to February) runs an active wormery. The Chelsea Physic Garden has a comprehensive “Compost Clinic” half-day course several times a year (chelseaphysicgarden.co.uk) and Brockwell Community Greenhouses sometimes run courses (brockwellgreenhouses.org.uk ).
Jeremy Prescott, Gardens sub-committee