May In The Garden
Plant summer hanging baskets under glass, incorporating water-retaining gel into the compost to make watering easier. Leave enough space in the basket to water generously. Hang out permanently next month, or put them out now but bring them in if frost threatens.
Ornamental grasses and bamboos should be divided or transplanted now, as growth commences. Large, tough bamboos will need a sharp spade and some force. The smaller, running varieties can be cut to the ground to produce a fresh crop of striped foliage.
Trim over straggly winter-flowering heathers after the last flowers have faded.
Plant out hardened-off annual bedding plants and settle them well in with a can of water.
Sweet peas can still be sown directly where they are to flower. They make a rapid seasonal covering for a less than pretty fence and coil their tendrils around chain-link with ease. Pick flowers regularly to keep them coming, they stop if allowed to go to seed.
This is the best time to buy summer bedding plants for perking up flowerbeds and containers, as garden centres still have plenty of choice.
Dahlias, gladiolas, tuberous begonias, lilies and cannas and other summer flowering bulbs can be planted this month. Gladiolas bulbs may be planted at 2 week increments until the first of July to provide you with cut flowers until the first frost.
Prune lavender and other grey-leaved shrubs Cut back hard but always above new growth.
Keep an eye on the roses, spray for aphids and other pests and diseases such as black spot.