Actually this is definitely too late! But one for next year. This one appeared at the start of november – which is pushing it a bit for planting over wintering manures – unless you live in very warm parts of the country. Ideally you should be planting September/October. But anyway – the resources are useful for next year.
It’s November, it’s cold – it’s your last chance to plant a winter compost crop! If you’ve got a clear, weed free patch of ground and you’re not planning to plant it up with anything until Spring the best thing you can do now is cover it up with a green manure. Nature hates bare soil. More nutrients are lost from soil through leaching (ie loss through wind and rain) when the soil is bare than from the growing of crops.
New research from Garden Organic – a four year field trial funded by the government – has found that growing grazing rye over the winter reduces loss of nitrogen from the soil by up to 97% compared to leaving the soil bare. This means that come spring your soil will be raring to go – plants will get a head start and you wont have to use so much nitrogen feed. As the cost of nitrogen fertilizers has risen by 15% in three years (the price being linked to the cost of oil) there’s also a financial incentive.
You may think it better to grow nitrogen fixing legume crops but legumes don’t fix nitrogen in the winter. Cereal Rye’s are much better because they grow quickly, getting a good start before winter really kicks in. Even if they die during the winter, the carbon they have stored during growth goes back into the soil, breaking down and feeding soil micro-organisms, whose numbers might other wise be greatly reduced without this supply of fresh organic matter. Because soil fertility is dependent on the activity of micro-organisms it really pays to have a spring soil filled with life.
Rye leaves and roots also produce chemicals that work as a natural herbicide, so this is the best compost crop to grow in soil overrun with weeds like fat hen and ragwort. Its vigorous growth helps to choke out these weeds. You must be careful though that the crop does not become a weed itself.
Cultivation is fairly simple. Prepare the bed you want to plant up as you would a seed bed. Sow the seed evenly and carefully according to the recommendation on the packet. Be aware that gaps left between rye plants will be filled by rogue weeds so make sure you cover as much ground as possible. Rake the seed gently into the soil. Pat it down with a roller, your feet or the end of the rake.
Unless you are saving seed for the following year you should cut the rye down before it sets seed in the spring. It has a strong root system and is hard to kill. The best way to organise its demise – which you must do to stop it taking over and to make room for your crops – is to cut very close to the ground in early April (when you can feel the seed head at the base of the stem) and then again two weeks later if it shows signs of re-growth. After this second cut the plant generally gives up and the roots decompose in the soil. So long as the seeds haven’t set you can incorporate all the organic matter back into the soil – either by digging it in – or just leaving it to decompose on the surface.
Resources
Growing Green: Organic Techniques for a Sustainable Future, Jenny Hall and Iain Tolhurst – quite technical but comprehensive guide for gardeners and farmers wanting to make the most of natural growing techniques.
The Complete Compost Gardening Guide – probably my favourite gardening book this year. Born in the U.S.A but suitable for British gardeners, this is easy on the eye and very informative.
www.organiccatalogue.com 0845 130 1304 – various sized seed packets, including one that will cover 7 square metres, enough for a small garden like mine. Booklet: Step by Step Green Manures.