THE BARE NECESSITIES FOR WINTER PLOTS
MOST vegetable plots and allotments tend to be left with lots of bare soil in winter. A better way of using spare space in the “off season” is to grow green manure.
This is the term for a range of agricultural crops, grown as living soil improvers. They are sown thickly in autumn so they cover the soil with a dense mat of foliage all winter to smother weeds and protect the delicate soil structure from rain.
Then they’re dug in early the following spring, releasing their nutrients into the ground.
Their roots take up nutrients (especially highly soluble nitrates) that would otherwise be washed away by winter rain.
Some green manure crops also have the same sort of root nodules as peas and beans, which house friendly bacteria that “fix” nitrogen from the air.
In both cases the nutrients are re-released into the ground when the plants are dug in and decompose. Meanwhile, leaves and stems break down to “roughage” that beefs up soil just like compost or well-rotted manure. Dig your green manure in and six weeks later the ground is ready.
For sowing in September go for tares or phacelia. Tares is a pretty crop with ferny foliage, purple pea-flowers and nitrogen-fixing roots. Phacelia is also pretty, with large sprays of misty-mauve flowers. Even though it doesn’t fix nitrogen, the plants provide a lot of worthwhile roughage.
Grow separately or together, scattering the seeds thinly and raking in for total cover.
For sowing until November try winter-grazing rye and field beans. The rye is perhaps best for improving heavyish or poor soil. Sown now it forms tough, tufty plants that need shearing short or mowing before digging in next spring.
It teams well with winter field beans, which are good nitrogen fixers.