As the equinox passes and we slip into autumn our kales, cauliflower, cabbages and leeks are already maturing in growing numbers and we have even started getting the first carrots into store. After a cold, wet start it has been a pretty good summer for us and most of our growers but a warm and sunny August with just enough rain is bringing autumn and winter crops forward at a slightly alarming rate; so far we are managing to clear crops without waste, but would welcome some cold nights to slow growth. Meanwhile we are busy ripping out the last of the cucumber plants which succumbed to the mildew that took hold in our polytunnels during June and July’s duller days. If we shut the tunnels to boost temperatures our tomatoes would continue ripening through October, but the flavour deteriorates rapidly with falling light, plus we would be late planting the salads that will provide balance in your boxes from December to March, so it is best to be brutal.
As indoor crops are cleared, outside our thoughts turn to protecting our soils from the looming ravages of autumn and winter. The soil is now at its warmest and most active with crop residues being quickly broken down by invertebrates, fungi and bacteria to release soluble nutrients which can be leached away by rain. To prevent this, we are planting mixtures of vetch, clover and grazing rye as green manures; the deep-rooting rye will grow vigorously through the winter, soaking up soluble nutrients and bringing them to the surface, while the leguminous species will fix nitrogen from the air. Such short term green manures will never be as good as not disturbing the soil at all, as in a forest or permanent pasture, but it is the best we can do while virtually all our vegetable crops are annuals, requiring us to create weed-free seedbeds every year.
For those with time, The Guardian published a great article on the potential of better soil management in sequestering carbon and combating climate change; Our best shot at cooling the planet might be right under our feet by Jason Hickel. He talks about how ‘regenerative farming’, where damaged soils are rebuilt with organic matter, might come to our carbon rescue. Let’s hope it’s the start of more respect for our soil.