Gardening jobs for August

Hopefully we'll have some warm, sunny weather so the garden is growing well. It's mid summer and there's often lots of watering to do, especially pots and hanging baskets.  It's a beautiful time of year to enjoy the garden and all the hard work you've done.

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Gardening maintenance for August

Water patio pots

Remember that plants in patio containers are dependent on you for their water as they'll get little benefit from any rain. Give them a good soak at least once a day in sunny weather.

Towards the end of the month, even containers which had controlled-release fertiliser added to the compost at planting time will start to run out of steam, so begin feeding once a week with a tomato feed.

Remove spent flowers as they will fade.

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Raise mower blades in dry spells

During dry weather, raise the blades on your lawn mower to allow the grass to grow a little bit longer. This will keep it greener and help retain moisture.

Don't panic if your grass does turn brown as it will soon green up again when the rain eventually returns.

Next month will be a good time to give your lawn a bit of TLC to get it back into shape after the hard wear it experiences in summer.

Jump straight to our reviews of our best lawn mowers.

Trim hedges

Midsummer is when most of us tackle our hedges as the new growth begins to make them look untidy. If you're using a hedge trimmer, start at the bottom of each side and work upwards in smooth, continuous swathes. Cut the top last.

You can save time by spreading a plastic sheet beside the hedge to catch the clippings. Brush or rake the clippings from the top of the hedge, as leaving them will make it look unsightly.

Read our reviews of our best hedge trimmers.

Compost grass clippings

If you don’t have a mulching mower, you’ll need to dispose of your grass clippings. It’s tempting to use the green-waste bin but it’s a waste of material for the compost heap. To avoid the clippings turning into a slimy mess, mix other materials into them, such as cardboard, and add a spadeful of soil as our trials have shown this helps them to break down.

Discover the best compost bins

Grow-your-own-veg jobs for August

Cut back strawberries

If you don't want to create new strawberry plants using runners, it's a good idea to cut back plants after they finish fruiting or they'll spread very quickly.

Remove any straw mulch and take out any weeds. New strawberry leaves will soon appear, so don't worry if your plants look a bit bare after you prune them.

Learn more about growing strawberries

Harvest veg

Catch veg while it's at its peak and harvest it regularly rather than leaving it to go woody or bitter-tasting. Don't get worried if you have more of something than you want to eat or store, as it's just as useful to recycle it by adding it to the compost heap.

Watch out for blight on potatoes and tomatoes

Watch for any signs of blight on potatoes and tomatoes. Keep leaves dry on undercover tomatoes as blight enters the plant when the leaves are wet.

The first signs of blight on tomatoes are large, dark-brown spots on the stems. Similar brown patches appear on the leaves but they are lighter in colour or grey. Some fruits develop dark ‘bruising’ and smell bad. If you spot an infected plant, pull it up. The first signs of blight in potatoes are small, dark areas, often on the edges of leaves. Infected tubers have brown and purple skin blotches that go into the tubers. If you spot blight on the leaves, cut off all the top growth to stop fungal spores spreading to the tubers underground. Then wait two weeks before lifting them.

Stop tomatoes

Stop tomato plants by pinching out the tops in early August to prevent any more fruit setting, which can't ripen before the cooler temperatures and lower light levels of autumn arrive. This way the plant will channel all its energies into the existing trusses of fruit and help them ripen fully.

Discover the best tomato varieties

Lift potatoes

Most potatoes are good to harvest by the end August, they keep as well or better in a sack as in the ground, with less pest damage. The foliage will begin to turn yellow when they’re ready to lift. The tubers won’t be swelling any more so there’s no advantage in leaving them in the ground. To lift the plants, either dig them up or get your hands around all the stems and pull.  Take the tubers off the roots and then put the top growth in the compost heap.

Find out how to grow potatoes

Plants-and-flowers jobs for August

Cut back lavender

Light pruning helps to keep lavender compact and rounded, rather than leggy and bare at the base. Use shears to trim away the old flowering spikes and the top 2-3cm of leaves. Our trial showed that you can prune in late summer or wait until spring as the timing makes no difference.

Discover the best lavender varieties and the best secateurs

Deadheading patio pots and hanging baskets

Many modern bedding plants are self cleaning and will drop their own dead flowers. For the rest, it’s a good idea to remove the blooms as they fade so that the plant keeps on producing new flowers. It will also keep the display looking neater.

See our round-up of the best plants for hanging baskets

Water camellias

The flower buds of camellias are formed during summer, so it’s important to water well to avoid them dropping off. Mulching around the plant with garden compost will also help to conserve moisture in the soil.

Give borders a boost

On free-draining and chalky soils in particular, your plants may be needing a boost by mid-summer so give them some general fertiliser, such as Growmore.