Early in the month, especially if it is warm and sunny, sow trays, pots or old growing bags with ‘cut and come again crops’ to harvest through autumn and into winter; think land cress, oriental salads, like pak choi, mizuna and mibuna greens plus lettuce, lamb’s lettuce, chicory and radish and imagine it is spring again. You can also use what is left from earlier brassica sowings and harvest them earlier as microgreens.
As temperatures drop at night, water greenhouse plants in the morning, avoid splashing water on the leaves and provide good ventilation during the day to reduce the chance of grey mould or powdery mildew as the air becomes damper.
Keep watering fruiting crops like chillies and particularly tomatoes to avoid ‘Blossom End Rot’ which flattens and blackens the end furthest away from the plant or fruit split. Both are caused by erratic water uptake. Remove any leaves which shade ripening fruit to hasten ripening.
Towards the end of the month, lift and pot up tender plants for overwintering in a frost-free glasshouse along with divisions of chives, lemon balm, mint and French tarragon. This will also extend the herb harvesting season well into autumn.
Put containerised plants outside in a sheltered sunny spot, covering them with fleece if temperatures are cool, then thoroughly tidy, clean and disinfect the glasshouse, with an eco-friendly disinfectant. Pull out any weeds that have been hiding behind pots, and plant debris so pests have nowhere to hide over winter.
Clean the glasshouse inside and out. Wear rubber gloves and goggles or safety glasses and take care on ladders. Work methodically, carefully and don’t over reach; whenever possible, work from the ground. An old vacuum cleaner is useful for sucking up debris resting on the glasshouse frame before you start. Rinse the glass to loosen dirt then wash the glass with a pressure washer or scrub with a long handled soft yard brush, using a plant label, old knife or credit card to remove moss or algae between the panes. Rinse off the glass, then dry and polish with a chamois leather or similar for a first class finish. While you are at it, clean the gutters, remove any plant debris, check that the down pipes are clear wedging a pan scrubber into the top of the downpipe stops them from being blocked by autumn leaves. Once you have finished, returned all your pots to their original positions on and under the bench.
Trusses of tomatoes can be cut and ripened on the greenhouse bench after you have finished cleaning.
Check the greenhouse heater to make sure it’s working before the onset of frost – it is worth seeking out a ‘bargain buy’ as a back-up, so you don’t lose precious plants. Remove the greenhouse shading or open blinds to increase light levels and feed your crops with tomato fertiliser to speed ripening, particularly towards the end of the month.
Remove any leaves showing signs of pests and diseases and treat tender containerised plants with biological controls for vine weevil before bringing them indoors. Keep pots weed free and benches clear of plant debris; plant hygene is always important but particularly at this time of year.
Happy gardening! Matt