Gardeners like to think that August is a “quiet month” but in fact it can be surprisingly busy with pruning, harvesting and taking advantage of the last chance to plant out spring crops.
There’s also a second wave of insect pests to deal with, not to mention a resurgence of weeds. Both can line up problems for the future if not dealt with now.
IN THE FLOWER GARDEN
Prune climbing and rambling roses once they’ve finished flowering - unless they’re repeat flowerers.
Dead-head bedding plants and perennials to encourage them to flower into the autumn and cut back faded perennials to keep borders tidy.
Prune all summer-flowering shrubs once blooms are finished and trim lavender plants once they have finished flowering, by up to a third.
Keep patio container plants well-watered and feed with liquid fertiliser every fortnight.
Wisteria will benefit from having laterals pruned back to a couple of buds.
IN THE VEGETABLE GARDEN
Feed high-potash fertiliser such as tomato food, not only to tomatoes but to sweetcorn, pepper, cucumber and aubergine plants once fruit starts to form.
Start harvesting maincrop potatoes when leaves go yellow and die back. Store in hessian sacks which keep out the light but allow ventilation.
Keep picking courgettes and runner beans or further flowering or fruiting will be inhibited. Garlic should also be ready for lifting now.
Spring-sown carrots and beetroots should be ready to harvest but can be left in the ground for a while longer.
When soil is moist, sow spring cabbage and winter lettuce. Mulch with compost as soon as seedlings are large enough.
Beware a second wave of cabbage white caterpillars on brasssicae and red spiders in the greenhouse. Daily spraying with warm water is said to be a deterrent.
Wasps will be a nuisance among ripening fruit so try hanging half-full jars of jam-sweetened water among the branches.