What to do in your garden in April

Aster Seeds - Milady Mix from Suttons

As we approach the middle of Spring, there’s plenty to do in the garden. Not only are the days getting longer, the soil is also beginning to warm up, which means there’s plenty to be getting on with in the potting shed.

April is a good time to sow your favourite vegetable seeds indoors, or directly outdoors if it’s warm enough, ready for a summer of bumper harvests. And if you want to fill your beds, borders, and containers with scent and colour, keep sowing your favourite flower seeds too.

Flowering plants in April

  • Plant out your autumn-sown sweet pea seedlings, or sow sweet pea seeds directly into their final flowering position now.
  • Sow hardy annuals indoors or directly outdoors. Browse through our full range of flower seeds for inspiration. Try cornflower, echium, helichrysum (strawflower), limnanthes (poached egg plant) and matthiola.
  • Sow half-hardy flower seeds in trays and keep them on a windowsill or in the greenhouse. Prick out seedlings when they’re large enough to handle and plant them into individual pots. Water them regularly and give a weekly feed.
  • Order young flower plants for delivery in May, ready to fill any gaps with colour.
  • Remove any faded flowers from early-flowering bulbs, especially daffodils.
  • If you want them to naturalise, then leave the flowers to die back naturally on snowdrops, crocus, muscari, scillas and other small bulbs.
  • In mild areas, plant dahlia tubers outside towards the end of the month.
  • Stagger the planting of your gladioli corms to prolong the flowering period.
  • Deadhead spring-flowering plants like primroses and pansies.
  • Place plant support frames over growing clumps of tall perennials now to encourage the new stems to grow through and hide the supports from view.

Vegetables in April

  • Now is the time to direct sow carrots, peas, beetroot, winter cabbages, broccoli, salad crops and much more. Browse through our full range of vegetable seeds.
  • Sow marrows, courgettes, pumpkins, squashes and tomatoes in a heated greenhouse or propagator.
  • If frost threatens, pull some fleece over your first early potato foliage. Plant second early potatoes this month.
  • Plant onion and shallot sets outdoors in well-spaced rows.
  • Order your tomato plants now for planting up indoors at the end of the month.
  • If your asparagus beds are at least 2-years old, then you can now cut and enjoy spears as they appear. Cut with a very sharp knife when they are 10 inches tall.
  • Sow herbs like dill, fennel, hyssop, parsley and thyme this month, undercover.
  • Thin seedlings in the vegetable patch, especially roots like carrot and beetroot.
  • If you have an established thyme plant, have a go at layering some creeping stems. Cover them with a fine layer of soil and once they’ve rooted, separate them and plant in pots or beds.
  • Sow sweet corn this month in modular trays undercover.

Fruit in April

  • Mulch around fruit trees with well-rotted manure or straw mulch.
  • Apple trees, pear trees, plum trees and cherry trees will start flowering in April. Don’t worry too much about flowers dropping. You only need 5% – 10% of the flowers to set fruit to have a good crop. In very cold or windy weather, protect blossoms with fleece.
  • Check for damage in your tree ties. Replace any that have snapped or re-tie to prevent damage to the trunk or the roots from too much movement.
  • Keep watering your newly planted fruit trees regularly.
  • Cover strawberry plants with cloches to speed up flowering and fruiting.
  • If any rhubarb flowers appear, cut them out near the base to stop them stealing food and energy from the plant. Harvest your forced early rhubarb this month when the stems are roughly 25cm in length.

Pots, baskets and containers in April

  • Plant begonia tubers in pots and keep them in the greenhouse – remember that the concave part of the tuber needs to be uppermost when you plant them.
  • Plant lily bulbs in pots so that you can move them around the garden when they flower.
  • Plant summer-flowering bulbs into pots for bright displays.
  • Plant up hanging baskets with specially selected hanging basket plants. Keep your baskets in a sheltered spot or in the greenhouse while the plants grow on.
  • Plant summer bedding into pots and containers this month. Shelter them in a greenhouse to move outdoors at the end of May/early June.
Lawn scarifier from Suttons

Image: Shutterstock

April lawn care

  • Rake any dead moss out of your lawn using a scarifier.
  • Apply lawn fertiliser to the whole lawn now.
  • Mow your established lawns keeping the blades fairly high, just nipping off the grass tips.
  • Carefully dig out any perennial weeds using a lawn weeding knife.
  • April is a great time for sowing new lawns and repairing bare patches in established lawns. Use self-repairing lawn seed to achieve a smooth and blemish free grass cover.

General April garden jobs

  • Warm up the soil prior to planting, or protect freshly sown seeds, using a fleece tunnel or a cloche.
  • Leave black plastic over beds for at least two or three weeks prior to planting to warm large areas of soil effectively.
  • Keep an eye out for slugs and snails — use slug and snail deterrents if necessary.
Bell cloche from Suttons

Image: Shutterstock

April pond care

  • Keep removing blanket weed as it appears with a stick or a rake so that it doesn’t take over. Try adding deterrents like barley straw bags to prevent outbreaks of algae.
  • Check the wiring and clean the filters of fountain pumps when you bring them out of storage away the winter before placing them back in the pond.
  • Refresh the look of your pond by adding new pond plants. Try a delicate native water lily or go for a marginal plant like a Louisiana iris for bold colourful flowers and tall strappy leaves.
Lead image: Aster ‘Milady Mix’ from Suttons
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