Lift crops which have finished growing and remove weeds from empty ground. Dress "bare" soil with manure, compost or plant green manures. If your compost heap is ready, empty out to make way for new material. If not turn if over every few weeks to improve the decomposition rate. If you want to put in new fruit trees/bushes this autumn, this is a good time to start researching and preparing ground for planting in Oct/Nov.
Last month for sowing perpetual spinach and oriental salads – they will be really worth it in the New Year when there's almost nothing else to eat, so get sowing! In the polytunnel/greenhouse sow lettuce, mustard, cress, basil, coriander, parsley, radish, dwarf early pea (e.g. 'Feltham First'), broadbean, cauliflower (seed, for planting next spring) rocket, chicory, onion seed and garlic. Outside sow white turnip seeds which will crop around Christmas, and autumn onion sets, e.g. 'centurion' and 'sturon'. Plant out strawberry runners as early as possible this month. Pot up some strong parsley plants in a large pot for winter use. Spring cabbage plants can be put in this month, in a sunny spot. Woody herbs such as sage, rosemary and thyme often root where their stems touch the soil – separate these out and plant to give them time to establish before growth stops for the winter.
Summer vegetables and fruit are joined by those more traditionally associated with autumn/winter, e.g. parsnips, swedes and celeriac. Lift your onions once the foliage withers and dies - leave them to dry out in the sun or in the polytunnel/greenhouse (but eat a few immediately to savour the taste). The great autumn tree fruits - apples, plums, pears – are now ripe. Pears should be picked when ripe and then stored for several weeks before eating. Continue to harvest salad leaves, tomatoes, shallots, radish, potatoes, carrots, turnips, beetroots, cauliflower, cucumbers, peppers and chilli-peppers, french and runner beans, courgettes, spinach, leeks, red cabbage, summer cabbage, aubergine, sweet corn. Go blackberry picking!