Here’s some advice about what to consider for your garden during August.
General tasks and garden maintenance
This is the month to really enjoy your garden; the scents, the colours, all the fruits and vegetables – and hopefully some sunshine. It’s a great chance to appreciate the work you’ve put into your garden over the year.
You need to remember to water and feed your plants regularly, especially those in hanging baskets, pots or containers as well roses and climbers growing against a sunny wall. Many plants will not recover from a drought. If it stays warm and dry, water saving tips include using bathwater and washing up water provided they are neither too dirty or oily.
Keep your pond topped up, free of pond weed and clean – green algae can be toxic to pets.
Keep on top of weeds in borders, the vegetable garden and all your pots and containers. Weeds not only look messy but use valuable moisture in the ground. Weeding on a sunny day will ensure weeds left on the surface dry out and die in the warmth.
Trees, shrubs and climbers
Deadhead all dying and spent flowers. Not only will your garden look much tidier, but the plant will be prevented from putting energy into the seed and may be encouraged to reflower.
When deadheading roses cut the stem down with sharp secateurs; just breaking off old flowerheads will leave the rose vulnerable to infection. It’s too late to spray roses for blackspot now – once established spraying will not help. Pick off infected leaves and burn. Do not put them on a compost heap where the spores will spread the disease.
Save seeds from the seed heads of bulbs, rock plants, trees and shrubs. Growing plants from seeds you have collected is rewarding, but you need to be vigilant; seed heads have a habit of ripening and popping. Collect when nearly ripe – just as they are turning brown. Snip them off, put them in a paper bag, label and hang somewhere cool, dark and dry.
Cuttings of bedding plants will root well at this time of year and quickly become strong enough to overwinter inside.
Train a long flexible shoot to ground level, cut a shallow sloping slit in it, dust the cut surfaces with hormone rooting powder, peg down to hold in place in soil enriched with a little potting compost and wait for it to root.
Keep hedges neat and under control, which helps both their appearance and good relations with the neighbours!
Mow regularly but you don’t need to feed or water – it’s a waste of time and will promote vigorous growth that may not stand up to the rigours of winter.
Flowers and containers
Plant autumn flowering bulbs and start to plant spring flowering bulbs, especially tulips, daffodils, iris and crocus. Always use the side bulbs of tulips and daffodils as they make perfectly good bulbs in their own right. Put poinsettias in the dark for 14 hours a day and full light for the remaining 10 hours to encourage the formation of those festive red bracts.
Keep picking. This is a month of abundance – so make the most of it. Pick vegetables when they are young – as they mature both flavour and texture become coarser. Some plants, such as courgettes respond to harvesting by producing more flowers and fruits right into the autumn.
Keep weeding and watering. Weeds look unsightly and steal essential water from your plants. Tomatoes need consistent watering to avoid blossom end rot (dark patches on their bottom ends) and many vegetables will bolt if allowed to dry out.
Damp down the greenhouse floor in the morning to create ideal humid growing conditions. Do not damp down in the evening.
This is the last month for sowing salads outside. Plant quick maturing crops, including lettuces, rocket, and sorrel. Plant onion sets and seeds such as spring cabbage, chicory, radish, fennel, turnips and winter spinach.
Harvest everything. Freeze if necessary, or swap with others who are short of your crops and long on ones you haven’t grown. Harvest onions, shallots and garlic when their necks collapse and turn brown and papery. Leave them to dry until the tops rustle like brown paper before storing.
Continue to earth up celery. Put a layer of paper between the stems and the soil and raise marrows off the ground to prevent them rotting. ‘Stop’ outdoor tomatoes and remove side shoots from outdoor and greenhouse tomatoes as well as the lower leaves to allow light and air to get to the crop. Feed with a high potash fertiliser. Beware potato blight if it’s hot and humid. Spray with a chemical fungicide if it looks like bad weather.
Harvest raspberries, blackberries, nectarines, early apples and pears. You can tell when they are ripe if they come off the tree with an easy twist and there are a couple on the ground. Prune summer fruiting raspberries, gooseberries, redcurrants, and blackcurrants.
Plant new strawberry plants and cut off the leaves of existing plants to within 3” of the crown. Burn the leaves and peg healthy looking runners so they root well.
Sow parsley for the winter, cut and freeze dry herbs pot up chives and mint for the winter. Lift a clump, divide and pot using multi-purpose compost. Cut back old foliage, water well, and then wait for your winter crop to appear.