Beware treacherous late frosts and keep vulnerable plants and new shoots protected at night if frost is forecast.
Don’t be tempted to put out tender bedding until the middle of the month and even then be prepared to cover it if necessary.
Continue with the spring cleaning. Hoe your borders to get rid of weeds before they take hold.
Dandelions are a nuisance at this time of year – if you don’t have time to deal with them terminally, at least chop their heads off before they set seed.
Water is a precious commodity – The trick with watering is to water thoroughly once or twice a week rather than little and often (containers etc do need watering every day).
Now the soil is warming up and things are starting to grow, add general purpose fertiliser before covering with mulch especially in borders, the fruit and vegetable patch and containers. If you have already mulched, draw it back (if possible), tease the soil a little, add fertiliser and replace the mulch.
Carry on removing moss and weeds from paths, terraces and drives and keep an eye out for pests around the garden. Try to keep the use of chemical controls to a minimum – they may kill off pests, but they also kill off the beneficial insects that prey on them such as ladybirds and hoverfly larvae.
Now is the time to deal with slugs and snails. They love tulips and delicacies such as the delicious young shoots of delphiniums and the like, so use pet-friendly slug pellets, drench the ground around hostas with liquid slug killer to exterminate slugs below the surface.
Keep an eye out for snails and pick them off, Birds are your friends here.
Protect new spring shoots from frosts and slugs….
Thin annuals to prevent them becoming spindly and leggy – a gap of 6 inches between seedlings is usually about right.
Tidy up spring flowering perennial- cut off the old foliage, lift and divide large clumps and replant with plenty of water and organic fertiliser.
Deadhead narcissi and tulips as they go over and sprinkle with bonemeal or liquid foliar feed. If you can bear it, allow them to die down naturally before clearing away the foliage and lifting and splitting towards the end of the month.
Cut back spreading and trailing plants such as alyssum and aubrieta to encourage fresh growth.
Tie in sweet peas using sweet pea rings or soft twine. Removing tendrils and side shoots will result in longer stemmed flowers.
Make sure pots and containers don’t dry out, especially if they are near a wall and in a sheltered position.
Plant up tubs, containers and hanging baskets for a blaze of colour throughout the summer – remember to harden tender plants off properly before exposing them to the elements.