Gardening in spring: tasks for April

A handy checklist of tasks for this month, from garden design expert Matt James.

  • Start mowing at least once a week.
  • Tie in climbing and rambling roses.
  • Feed and water houseplants more often now they’re actively growing.
  • Split overgrown bamboo – you’ll need a sharp spade and an old saw.
  • Stake tall perennials such as delphiniums and sunflowers with ‘grow through’ supports.
  • Create new container displays and water well in dry spells.
  • Sow half-hardy bedding plants in seed trays or cell trays undercover. If there’s space, pot plug plants into larger pots – cheaper than buying bigger pot plants in a month’s time.
  • Plant up summer baskets and grow undercover before positioning in late May.
  • Clear out ponds: take out planting baskets and fish (keep in buckets of old pond water), bail out the water, remove sludge and refill. Rainwater is best, but let tap water stand for a week before putting fish back in.
  • Plant new pond plants using special pond baskets from garden centres.
  • Last chance to create new lawns using turf without a sprinkler.
  • Deadhead spring-flowering bulbs.
  • ‘Earth up’ potatoes when shoots are 15cm tall.
  • Sow rocket, cut-and-come-again salads, summer lettuce, beetroot and carrots in shallow drills (trenches) outside.
  • Sow winter brassicas outside. Thin and space seedlings to the correct distance when three leaves have grown.
  • Protect tender vegetables from late frosts – keep horticultural fleece on standby.
  • Watch out for early pests and diseases – hit them hard now to avoid problems later on.
  • Sow tomatoes, runner beans, basil, green pepper, marrow, courgettes and sweetcorn in individual modules undercover for planting after the frost. 
  • Use fine Environmesh to protect young carrots from carrot root fly.