April gave us a real variety of weather but the warmer days at the end of the month have certainly given everything a welcome boost. May is recognised as the last month of Spring, we are now well on our way to early Summer and our dormant gardens have now transformed themselves into a world of new growth and greenery.
Some plants to buy or enjoy in May
Euphorbias, Wallflowers, Honesty, Tulips & glorious Peonies, Nicotiana, Honeysuckles, sweet peas & the fragile, stunningly-fragant Lily of the Valley are but a few of the lovely flowers to enjoy this month.
Azaleas and Rhododendrons are also at their best in May together with Deutzia, Cornus (flowering dogwoods) and Viburnum plicatum.
General Garden maintenance
• Hoe or hand-weed beds weekly, to prevent weeds establishing themselves
• Put supports in place for perennials that are prone to flopping, such as top-heavy peonies or phlox
• Apply nitrogen-rich summer lawn feed to encourage green growth
• Trim topiary and shaped shrubs regularly to promote bushy growth and keep them neat
• Sow grass seed or lay new turf by the end of this month
• Check shrubs for nests before you start any pruning, to avoid disturbing nesting birds
• Clean out and scrub bird feeders regularly to maintain hygiene
• Build sturdy wigwams and supports for climbers such as runner beans, sweet peas and morning glory
• Watch out for aphids on shoot tips and young foliage, and wipe them off or spray with a shop bought solution
• Scoop out pondweed, blanketweed and algae from ponds
• Paint or treat wooden garden furniture ready for summer
Flowerbeds and Pots
• Prune spring shrubs eg: forsythia and chaenomeles, after flowering to keep them compact
• Plant out dahlia tubers and cannas after all risk of frost has passed
• Tie in the new shoots of climbing plants, including clematis, wisteria and honeysuckle
• Plant up hanging baskets, but keep in a greenhouse or porch for a few weeks to establish, before putting outside
• Apply liquid feed to tulips, daffodils and other spring bulbs to encourage a good display next year
• Plant out summer bedding and tender annuals, including sunflowers, cosmos and nasturtiums, after the last frost
• Check lilies and fritillaries for scarlet lily beetles and their larvae, as they can rapidly strip plants of all foliage
• 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 annuals to encourage bushier growth
• Add interest to shady borders or corners by planting a selection of hostas and ferns in the ground or in pots
The “Chelsea Chop”
• The Chelsea Chop is a way of cutting back herbaceous and perennials plants to make them bushier, with more stems and more flowers. It’s good for plants which can get too tall or leggy later in the year, such as Nepeta, Phlox, Alchemilla and daisy-flowered perennials like Asters and Michaelmas Daisies.
• By chopping of the top of the stems in late May, growth will be checked and the plant will throw out more shoots and flower later. The Chelsea chop is really a light prune, and the result is a more compact plant which will flower slightly later.
• Traditionally done in late May to coincide with the time of the Chelsea flower show, the idea is to prune the plant back by about a third, by reducing the length of the plant stems. You can either chop the whole plant, or selected plants in the group, or individual stems on the plant to stagger flowering. Whilst May is the traditional time, it depends on the growing season as the plant needs to have put on a decent amount of growth to be reduced by the Chop.
Fruit and vegetables
• Earth up potatoes, covering the shoots with soil as they appear
• Start sowing dwarf and climbing French beans, as well as runner beans, directly outdoors in warm weather
• Pick rhubarb stems and water plants with liquid feed
• Start hardening off tender young plants, such as tomatoes and courgettes, ready for planting out in mild areas
• Sow batches of salad leaves and stir-fry crops every few weeks to provide continuous pickings