What to do in your garden in May.
The end of May is the traditional time to start planting half-hardy annuals and other tender plants in the garden, due to late frosts usually having come to an end by then. It makes the Spring Bank Holiday weekend the starting pistol for so much buying and planting of bedding plants, and the busiest time of the year for us. There are plenty of things you can be doing all through May in preparation for this time though, as well as in maintenance of hardier plants and crops. Don’t forget though in the midst of all this work, to stop and just enjoy your garden, which at this time of year can be a magical place.
Harden off tender plants. If you have a greenhouse filled with plants ready to go out when the frosts are over, be it trays of young plants grown from seed, hanging baskets ready planted, or tender vegetables such as tomatoes and cucumbers, bring them outside in the morning and take them in around early evening. Do this every day for at least 7 days before planting out in order to acclimatise them.
Earth up potatoes. Once your potato plants are 10cm high, draw soil up around them to protect the young foliage from frost and developing tubers from the light which can turn them green and poisonous. If you are growing them in rows, earthing up will form a ridge around the potato plants. Potatoes planted in containers or bags can have extra compost added to them which works in the same way.
Trim Lavender plants. Established Lavenders need a chop at this time of the year to keep them compact and prevent them turning woody. With secateurs, take off any remaining flower stems from last year, and about 2.5cm of the current year's growth, making sure to leave some green growth on the plant, as lavenders will not re-grow from bare stems.
Plant Pansies, Violas & Senetti. Though Pansies and Violas are usually associated with winter bedding, they make a great choice through the summer too, with the added benefit of being hardy enough to be planted out now and get a head start. Senettis are a real touch of summer, with their brightly coloured daisies, and make great pot plants – and are ready to go out now!
Hang Pheromone traps in fruit trees. If you have Apple or Plum trees, now is the time to set pheromone traps which can be used to monitor the amount of Codling Moths (apples) or Plum Moths in the area. This gives the fruit grower the best information on when to spray, should there be the need.
Tie in sweet pea plants. Climbing Sweet Peas will now be sending out stems with tendrils ready to grip any support they can find. Help them in the right direction using wire plant support rings, securing them to your canes, obelisk or trellis.
Plant out Brassicas and Leeks. Young plants of brassicas (Cabbages, Broccoli, Cauliflower, Kale etc) and Leeks can now be planted out into their final position. Protect brassicas with crop protection mesh to deter pigeons from feasting on the tender leaves.
Keep weeding! Beds and borders need checking over every couple of weeks for new weeds. Hoe off annual weeds, whilst carefully digging out perennial ones, particularly if they have a deep tap-root such as Dandelion.
Thin out vegetable seedlings. Carrots, Lettuce, Beetroot and other vegetable seedlings that have been direct sown can be thinned out now to allow those seedlings that are left more room for growth and less competition for water, nutrients and light. Don't thin too many at once, leave some in case of slug damage. Carrots should be thinned at the start or end of the day when it's cooler - the scent of uprooted carrot seedlings can attract carrot root fly. Consider protecting them with insect protection sheet straight after thinning.
