Garden tasks for April, 2015

Flower garden

Cinneraria
Cinneraria

April is a busy month in the garden – replace your tired summer-flowering annuals with primulas, cinerarias, nemesias, Iceland poppies, calendula, stock, pansies, polyanthus, snapdragon and hollyhock.

Sow seeds of aquilegia, viola, linaria, cornflower, godetia, snapdragon, dianthus, lobelia, sweetpea, cineraria, English daisy, statice, stock and alyssum.

Biennial seedlings, like Canterbury bells and foxgloves that you want to flower next spring or summer, should be planted now.

Carry on planting your spring bulbs – the sooner you get them in the better. Start planting lilies and tulips at the end of the month.

Give straggly perennials a light prune to tidy appearance as they finish flowering, but leave their foliage to die down naturally.

Plant new perennials and shrubs to fill gaps left by plants that failed to make it through the heat and dryness of summer.

This is a good month to plant cold-hardy evergreen trees and shrubs. Soils should be moist enough now for them to settle in without undue stress.

Avoid feeding plants late in the season – this will encourage soft, sappy growth that’s much more vulnerable to damage by frost and wet conditions.

Fruit and vegetable garden

Harvest late summer vegetables such as potatoes and onions, and store in a cool, dry place. Pick butternut, kumi kumi, pumpkins and squash now for winter use – pick carefully leaving at least a little stalk.

Pick tomatoes as soon as they show any sign of colour and ripen indoors.

Sow seeds of beetroot, broccoli, broad beans, cabbage, carrots, onions, radish, spinach, swedes and turnips.

Plant out seedlings of broccoli, brusssel sprouts, cabbage, cauliflower, celery, leeks, lettuce, silverbeet and spinach.

Watch out for earwigs and snails on seedlings. Trap earwigs in small boxes, tubes or flowerpots filled with straw.

Pick kiwifruit as soon as they soften – the riper they are when picked the sweeter the flavour.

Collect and store the last of the pears and apples – apples are ready to be harvested when, if slightly lifted, they come away from the branch.

Passionfruit vines may still be bearing – fruit can be picked as soon as it begins to turn purple.

Treat citrus trees with a copper spray.

Lawns

April is the best month for sowing new lawns and rejuvenating existing ones – even tidy lawns will benefit from a dose of lawn food. Choose one designed for use in autumn – as growth slows, you need a low-nitrogen mix which encourages strong resilient roots rather than lush top growth.

Second thoughts

Clean out organic material from ponds to discourage a nutrient-rich soup that will attract algae next year.

Pot up hyacinth bulbs and amaryllis. If you plant them now you’ll be able to enjoy them flowering indoors during the winter months.