Gardening Tasks for May

May is the peak month for gardening, and here are some suggestions for jobs to do in the garden in this busy month. Just remember to find time to relax and enjoy your garden too.

• Prune spring flowering shrubs, such as Forsythia after flowering to keep them compact. Prune out the stems that flowered to encourage more flowers next year
• Pot up Dahlia tubers and keep indoors before planting after all risk of frost has passed – usually end of May at the earliest in the Scottish Borders
• Tie in or tuck in the new shoots of climbing plants, such as Clematis, Wisteria and Honeysuckle, to their trellis, wires or obelisks
• Continue sowing annual plant seeds, such as California Poppies into gaps in borders for late season colour
• Plant up hanging baskets with annual plants, but keep in a greenhouse or porch for a few weeks to establish, before putting outside in early June
• Towards the end of the month, and depending on the weather forecast, plant out summer bedding plants in beds and containers. It’s useful to have a roll of fleece handy just in case the overnight temperatures dip unexpectedly.
• Remove old spring bedding plants, such as Wallflowers, Pansies and Primroses.
• Harden off tender plants raised indoors, but bring them back in at night to protect from late frosts
• Pinch out the shoot tips of bedding plants and young plants, such as Fuchsias, to encourage bushier growth and prolific flowers later on
• Fill in any gaps in the garden with new plants and water well if it’s a dry Spring
• Put plant supports in place to prevent taller plants such as Lilies, Delphiniums and Campanulas flopping onto other plants
• Earth up emerging potatoes, by pulling soil up and over the shoots to encourage more productive roots
• Sow tender vegetable plants such as Sweetcorn, Cucumber and Courgettes ready for planting out later on
• Keep an eye on slug activity around vulnerable plants and apply your preferred deterrent – either pellets, egg-shells, wool pellets, or traps filled with grape juice – or whatever method works for you.

• Start sowing Dwarf and Climbing French Beans, as well as Runner Beans indoors at the beginning of the month, ready for planting out in June.
• Harvest Rhubarb stems as they develop, and feed well in order for them to build up vigour ready for next year.
• Sow batches of lettuce, leaves and stir-fry crops every few weeks to provide continuous pickings
• Hang pheromone traps in apple and plum trees from May to July, to control pests such as codling moths
• Thin out vegetable seedlings, from earlier sowings to ensure you get healthy, strong-growing plants
• Open fruit cage doors or lift some of the netting to ensure pollinating insects can get access to the flowers
• Remove all strawberry runners, so plants put their full energy into fruiting. You could pot them up to make new plants.
• Water crops regularly as the weather starts to warm up and if there’s a lack of rain
• Tie the stems of indoor tomatoes, cucumbers and aubergines to canes as they grow and feed regularly
• Check plants regularly for pests, on shoot tips and the underside of leaves, and treat with controls if necessary
• Put up shade nets or apply Cool Glass to greenhouses to lower daytime temperatures and reduce scorching and open doors and vents on warm days, but close them in the evening as nights can still be cold
• Keep pricking out seedlings as soon as they get their first true leaves, to avoid overcrowding and fungal diseases
• Scoop out pondweed, blanketweed and algae from ponds and water features. Apply Feature Clear to water features that don’t contain any plants or fish, to keep them running clean
• Plant out pond plants such as water lilies, marginals and oxygenators to achieve a balanced planting which will help keep the water clean and healthy
• Introduce new ornamental fish to your pond, ensuring you have enough leaf cover to give them somewhere to hide from herons
• Put soft tops on the tips of all canes, in borders, veg plots, pots and greenhouses, to prevent injury to eyes
• Apply wood treatment to wooden garden furniture and planters to condition it for summer and the extend their useful life
• Apply nitrogen-rich summer lawn feed to encourage leafy growth
• Mow grass pathways or mazes through wildflower and meadow areas areas so you can walk in among the flowers
• Keep on top of the weeds by hoeing bare soil regularly on warm dry days and hand-weed beds weekly, so weeds don’t have time to establish and set seed
• Trim topiary regularly with a clean pair of hedge shears, to promote bushy growth and keep it looking neat
• Sow grass seed or lay new turf by the end of this month, to create a new lawn or to repair damaged patches
• Mow grass regularly, making sure not to cut too short to increase drought resistance, and tidy lawn edges weekly with a sharp pair of edging shears
• If you are continuing to feed the birds, make sure you clean and disinfect feeders weekly to avoid spread of diseases.
• Build sturdy wigwams or purchase supports for climbers such as Runner Beans and Sweet Peas