Carpeting the allotment
Further to conversations on the CVAA members home page, I have been asked by some plot holders to look into the use of carpet as a weed suppressant mulch. Here is a summary of what I have found – I hope it is useful.
There is a lot of debate on the use of carpet as a weed suppressant mulch. There is support for its use as a cheap alternative to weed suppressing membrane, but the overall view is that its use should be limited to as short a time as possible or not used at all. In fact many allotment organisations have banned its use entirely, including Pittington Parish Council and DCC. The main issue is that of pollution. Weeds will grow through the carpet as it weathers and rots and it will fall apart as soon as you try to pull it up, leaving fibres and stringy nylon in the soil, which causes problems to gardeners and wildlife alike. Good quality wool carpet still has nylon in the weave. The major organic gardening publications have recently changed their advice on the use of carpet and no longer recommend using any carpets on the garden or allotment. It was felt that where previously it was advised that only natural fibre carpets could be used, many carpets now are treated with moth repellents and fire retardants. Even if you know the fibre content of old carpet you are unlikely to know what other treatments it may have received that may pose a problem especially if the carpet is left in place to decompose. There are many other safe alternatives such as cardboard over newspaper, weed control fabrics and permeable mulch matting that can be reused to keep areas covered when not in cultivation.