May has arrived and the days are getting warmer and longer. Summer is on its way and it’s time to tidy up spring plants, plant out summer flowers and get planning for autumn.
If you’d like to know what to sow and grow this month, check out this page. Or read on for your comprehensive list of May’s other garden jobs:
May's the perfect time to air your greenhouse out Image: val lawless
Start planting out summer bedding towards the end of this month in warmer parts of the country.
Look after your finished spring bulbs for next year. Once they’ve gone over, resist the temptation to cut back the foliage. Instead, let it die and break down on its own and add liquid fertiliser all around the clumps. This will give you an even better display next spring.
Remember to open greenhouse vents and doors on warm days. You can also damp down your greenhouse on hot days to increase humidity and deter red spider mites.
Optimise your watering regime - watering early and late to get the most out of your water - and start collecting and recycling water whenever possible.
In the flower garden
Keep your lavender plants healthy with regular pruning Image: Lithiumphoto
• Trim back spreading plants such as aubrieta, alyssum and candytuft after they’ve flowered, to encourage fresh new growth and more blooms.
• Lift forget-me-nots to prevent heavy self-seeding and reduce spreading.
• Prune penstemons now - cut all the old shoots back to the base, providing there is new growth at the bottom of the plant. If there are no new shoots at the base, cut just above the lowest set of leaves.
• Take cuttings of tender perennials, such as fuchsia, argyranthemum and pelargoniums (geraniums). The new shoots of hardy perennials can also be used for cuttings.
• Take softwood cuttings of shrubby herbs (such as sage and lemon verbena).
• Prune out overcrowded and dead stems of early-flowering clematis (C. alpina, C. cirrhosa, C. macropetala, C. armandii, and their cultivars) after flowering.
• Tie in climbing and rambling roses. Laying the stems horizontally will help to produce more flowers.
• Remove duckweed and blanket weed from ponds, and thin out submerged oxygenators. Lay any removed weed beside your pond overnight to allow insects, snails and other pondlife to escape back into the water.
• Keep on top of weeds to prevent them spreading.
• Clip evergreen hedges now.
• Control the heat in your greenhouse with blinds or shade paint.
• Hang fly traps throughout the greenhouse to monitor levels of whitefly, thrips and other pests.
From your armchair
Write down what you sow & grow throughout the year Image: Abacucu
• Keep a diary of which seeds you’re sowing and planting to help you stay on top of things throughout the year.
• Take time out from the all your hard work to relax and enjoy the garden now that the warmer weather has arrived!