This month is a good time to sow peppers in a heated propagator or on a windowsill indoors at a temperature of 21-27C (70-80F), to give them a head start for summer.
When large enough to handle, the seedlings can be pricked out and potted on to individual small pots to grow at 16-19C (60-65F). Harden them off carefully as peppers are extremely frost sensitive.
They can be planted in an unheated greenhouse from late May to early June, or outside, preferably in a sheltered spot, in mid-June.
Water them in well after planting and then sparingly until they are starting to flower. Support them with canes and apply a liquid tomato feed once a week once the first flowers open.
Here's what to do in the garden now
Sow under glass quick-growing perennials to flower this year
Begin to feed plants in established borders using a controlled-release slow-acting fertiliser, taking care not to get the liquid on to new foliage
Spray nectarine and peach trees to prevent or eradicate peach leaf curl disease
Cut back hedges before birds start to nest in them
Prune large-flowering clematis (group 3) including C. viticella and hybrids such as C. ‘Jackmannii’, taking stems back down to 25-45cm (10-18in) above ground level
Check if rain-sheltered trees, shrubs and climbers in containers are dry and, if so, water containers from time to time
Check seedlings growing indoors have plenty of natural light so they don’t become leggy
Cut back deciduous buddleias, lavatera, hary fuchsias and ceanothus, which produce their best show of flowers on wood made from spring onwards
If it’s not too wet or frosty, brush over lawn surface that has become covered in worm casts, using a besom or brush
Scoop out leaves, twigs and other debris from guttering on conservatories, greenhouses and garages