Gardening calendar for April and May
Lawns: Sow seed and protect. Mow established lawns with blades at medium height. Apply a fertiliser, followed a fortnight later by a selective weedkiller.
Shrubs: Transplant evergreen trees and shrubs. Layer magnolias, hamamelis, Hydrangea paniculata and Chimonanthus praecox. Prune lavender, santolina and Forstythia suspensa.
Roses: Apply a mulch. Weedkiller can be used to keep down weeds.
Rhododendrons: Remove faded flowers. Mulch with peat or garden compost. Chrysanthemums: Harden off cuttings. Dahlias: Plant tubers. Take cuttings of tubers started into growth in March.
Carnations and pinks: Feed border plants with general fertiliser. Support floppy types.
Annuals: Complete sowing of hardy and half-hardy annuals. Move seedlings taken from previous sowings to a cold frame. Watch out for aphids.
Bulbs: Continue to plant gladioli and acid-antheras. Dead-head early bulbs.
Lillies: Stake tall lillies as flower buds form. Water plants: Plant water lilies and other plants. Overgrown lillies can be lifted and divided. Prick off seedlings of bog primulas.
Heathers: Lightly shear winter heathers. House plants: Increase watering and give regular feeds. Pot on plants that are root bound; divide if suitable.
Fruit: Feed with Nitro-chalk or sulphate of ammonia. Protect trees in flower from late frosts with netting. Begin spraying as needed, but not during blossoming.
MAY
Lawns: Mow at least once a week. Apply weedkiller if necessary. Feed poorly growing grass with sulphate of ammonia at ½ oz per square yard; water copiously afterwards. Spike badly drained areas.
Shrubs: Prune early-flowering shrubs such as
Kerria japonica and Prunus triloba.
Roses: Spray roses against pests and disease and apply a general rose fertiliser.
Chrysanthemums: Plant outdoor-flowering plants early in the month. Stop the plants about the middle of the month.
Dahlias: Plant out young dahlias from cuttings after danger of frost is over.
Annuals: Plant out half-hardy annuals after risk of frost has passed. Sow biennials – Canterbury bells, foxgloves, sweet Williams and wallflowers.
Bulbs: To make room for bedding plants, lift bulbs that have finished flowering and heel them into spare ground.
Irises, Rock Plants, Heathers: Remove faded flowers from irises, spring-flowering rock plants such as gentians and saxifrages and winter-flowering heathers. Top dress heathers with peat.
House Plants: Water more freely; give weekly liquid feed to older plants.
Fruit: Feed figs with liquid manure and mulch. Start de-shooting fan peaches and nectarines and thin when fruits are the size of marbles. Water well in dry spells. Put straw round strawberry plants.