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What to do in the garden this month

What to do in the garden in July

There's always something to be doing in the garden, whether it's pruning, tidying or sowing, so we've put together our top gardening tasks for July.

flower garden daffodil In the flower garden

  • • Cut back faded perennial plants to keep borders tidy.
  • • As your Penstemon flowers fade, cut them back to just above a bud to encourage more flowers.
  • • Cutting back growth in hanging baskets can encourage new flowers and foliage and will revive the display. Make sure you that feed your baskets well after doing this.
  • • Cut back hardy Geraniums and Delphiniums after the first flush of flowers to encourage new growth and further blooms.
  • • Continue to tie in and train new growth on climbing plants.
  • • Prune Wisteria now. Just remove the whippy side-shoots from the main branch framework to about 20cm from their base (about five leaves from the main stem).
  • • Prune lupins  to encourage further flowers.
  • • If you need to prune your deciduous Magnolia, now is the best time to do it.
  • • Divide clumps of Bearded Iris  now so they have time to form roots and flowers buds for next year before the cold weather arrives.
  • • Take cuttings from your favourite tender plants for over-wintering indoors. Cuttings can also still be taken from shrubs and herbaceous perennials.
  • • Dead-head bedding plants and perennial plants to stop them self-seeding and to encourage further flowering.
  • • Dead-head your roses to keep them looking tidy. Leave the flowers in place if your rose produces attractive hips (seed pods).
  • • Dead-head sweet peas regularly to keep them blooming. Water daily in dry weather.
  • Capture seed heads from dandelions and other weeds. Collect them before they get a chance to release their seeds and spread throughout your garden.
  • • Keep an eye out for pests on plants, early treatment is best.
  • • Stop rust damaging hollyhock foliage by pruning out affected leaves and/or spraying with a fungicide.
  • • Look out for Clematis Wilt. Symptoms include wilting leaves and black discolouration on the leaves and stems. Cut out all affected material and dispose of it in your household waste.
  • • Now is a good time to spray ground elder, bindweed and other persistent weeds with a glyphosate-based weed killer as the plants now have lots of leaf surface area with which to absorb it.

vegetable garden carrot In the vegetable garden

  • • Plant second cropping potatoes now to give you new potatoes for Christmas. Plant your Christmas potatoes in pots or bags which can be brought under cover before the first frosts.
  • • Pepper plants will benefit from being potted on into progressively larger pots.
  • • Train cucumber stems upwards instead of trailing over the ground, to make the most of the space available. Simply tie in their long stems to vertical wires or a wigwam of poles.
  • • If you're growing aubergines pinch out the growing tip once they have 5 or 6 fruits. Pick fruits while they are young. You can expect to start harvesting in mid to late summer.
  • • Nip off the growing tips of squash and courgette to encourage branching.
  • • Pinch out tomato side shoots each week. Cut off any leaves growing below the lowest ripening fruit trusses to improve air circulation and prevent diseases.
  • • Boost your tomato crop by regularly feeding them with dilute tomato fertiliser once a week. If leaves look pale and yellow feed more regularly.
  • Feed crops with a general purpose fertiliser.
  • • Apply a high-potash fertiliser once fruits start to form on peppers, cucumber and tomatoes. You can use this on sunflowers too.
  • • Harvest garlic when the tops start to bend over and yellow. To find out more about harvesting and growing garlic read our 'how-to' guide.
  • • Pick your courgettes while they are young. Regular picking encourages more fruit.
  • • Encourage more marrows by harvesting regularly. Marrows that form in July and August should reach a good size by autumn. Let their skins harden in the sun before cutting them later in September or October. They can be stored into winter.
  • • Pick, dry and freeze herbs for using later in the year.
  • • Resist the temptation to harvest more rhubarb stems. This allows the plant to build up reserves for next year.
  • • Pick runner beans regularly to prevent them becoming stringy and to make room for developing pods. Leaving mature pods on the plant can prevent further flowers forming and reduce your crop.
  • • Harvest beetroot, peas, carrots, chard, potatoes, salad leaves, lettuce and tomatoes  this month.
  • Water your fruit and vegetable crops daily in warm weather. Try to ensure that they are consistently moist.
  • • Use grass clippings as a mulch around potato plants to stop tubers near the surface from turning green. Alternatively earth up your potato plants as they grow. If you're growing potatoes in bags, gradually add more compost until the bag is full.
  • Control slugs to prevent them damaging your crops. Try using a natural pest control to reduce numbers.
  • Tackle blackfly on broad beans by pinching off any affected growing tips.
  • • Check for cabbage white butterfly eggs under brassica leaves and squash any that you find.
  • • Clear away any diseased and spent foliage on and around your vegetable plants to keep them healthy.
  • Clear weeds regularly, as they compete with your crops for nutrients and water.

fruit garden strawberry In the fruit garden

  • Thin out the fruits on your fruit trees to produce good sized crops. This also helps to prevent brown rot.
  • • Protect any developing fruits from birds and squirrels by placing netting around your plants.
  • • If you have plants fruiting in containers, make sure you give them a high potash liquid feed to keep plants healthy and productive.
  • Feed lemons and other citrus fruit trees throughout summer with a special citrus fertiliser.
  • • Treat apple scab with a fungicide. Always read the manufacurers label to check the suitability for use on edible crops.
  • • Check the leaves of gooseberry bushes for sawfly larvae, which can completely strip the foliage in a matter of days. Jet them off with water or pick them off by hand.
  • • Peg down runners on your strawberry plants to create more plants for next year. If you don't need more plants simply remove the strawberry  runners completely.
  • • Maximise your fig crop by pinching out the tips of sideshoots after they have developed five leaves.
  • • Prune your plum, apricot, peach and cherry trees now. Pruning these species in the summer reduces the risk of these trees getting silver leaf disease.
  • • If you've trained your apples and pears as cordons, fans or espaliers, give them their summer prune now to maintain a good shape.
  • • Prune the fruited stems of your blackcurrant bushes after harvesting.
  • Raspberries are shallow rooted so they will appreciate being watered generously in hot, dry weather.

In the greenhouse greenhouse In the greenhouse

  • Check plants daily. Water first thing in the morning or in the evening to reduce water loss through evaporation.
  • Harden off and plant out any plug plants that you have been growing on.
  • • Damp down your greenhouse on hot days to increase humidity and deter red spider mites.
  • Open vents and doors daily to provide adequate ventilation.
  • • Use blinds or apply shade paint to prevent the greenhouse from over-heating in sunny weather.
  • • Try hanging sticky traps to catch flying pests and help determine which pest control is needed.
  • • Tidy up fallen leaves and flowers to discourage the spread of fungal disease.

 Looking after your lawn lawnmower Looking after your lawn

  • • This is your last chance to feed your lawn with a special lawn fertiliser to encourage healthy green growth.
  • Water your lawn during hot weather, particularly newly seeded or turfed lawns. Do not allow new lawns to dry out.
  • • If you are experiencing prolonged dry weather, set your mower blades higher to reduce stress on the grass.
  • • Warm weather encourages rapid weed growth - apply specific lawn weed killer to tackle this problem.
  • • If your lawn is infested by ants, brush out the nests on a dry day. Always brush them away before mowing.
  • Recut any lawn edges if needed. Try installing lawn edging to make future maintenance easier.

From your armchair armchair From your armchair

  • Order perennial plants online now ready for autumn delivery.
  • • Think about which bulbs you would like for next spring - now is the time to order ready for autumn planting.
  • Make a note of your gardens pros and cons at this time of year to remind you of any changes that you need to make for next year.

Other garden jobs wheelbarrow Other jobs about the garden

  • Try watering the soil around the base of plants rather than the foliage. Make ‘pools’ around individual plants so that the water is directed straight to the roots where it is needed.
  • Water your containers and baskets thoroughly in hot weather. Continue to feed them with a balanced liquid fertiliser every 2 to 4 weeks.
  • Use water butts instead of tap water as often as you can when watering your plants.
  • • Turn the contents of your compost bins every month to keep it well aerated.
  • • Keep bird baths topped up in hot weather.
  • Remove floating blanket weed from ponds by twirling it around a stick or garden cane. Before composting it, pile the weed close to the pond for a few hours so any creatures caught up in it can crawl back into the water. Try using Pond Wizard to help clear weed from your pond.
  • • Keep an eye out for powdery mildew on plants. Remove any affected parts and spray with a fungicide to prevent further spread.
  • • Look after your aphid eaters - ladybirds, hoverflies and lacewings feast on greenfly and blackfly so it is worth protecting them.
  • • Look for aphidson the underside of leaves - rub them off by hand or spray with an insecticide to prevent them multiplying. Alternatively try using a natural pest control such as Lacewing larvae.
  • • Keep an eye out for scarlet lily beetles on your lilies - remove and crush any you see. Also check for the sticky brown larvae on the underside of leaves.
  • • If your plants are wilting for no obvious reason then check for vine weevils by tipping your plants out of their pots and looking for 'C' shaped creamy maggots amongst the roots. Treat with nematodes if vine weevils are spotted.
  • Prevent slugs attacking your young plants by using nemaslug. For container plants try using copper tape.