May Gardening Advice and Tips

May Gardening Jobs: Bursting into Bloom!

Welcome back to the garden as May arrives, bringing with it a vibrant explosion of growth and colour! The hard work of spring preparation is starting to pay off, but there are still plenty of exciting tasks to keep us busy and ensure a flourishing garden throughout the summer.  Here's your essential to-do list for May gardening in the UK:

Sowing & Planting:

• Direct Sow Hardy Annuals: Now is the perfect time to sow seeds of hardy annuals like American Poppy, Bird's-eye, and Corncockle directly into their flowering positions.  Ensure the soil is well-prepared and keep it moist until germination.
• Plant Out Summer Bedding (Towards the End of the Month in Warmer Areas): Keep a close eye on the forecast and in warmer regions, you can start planting out tender summer bedding plants such as Busy Lizzies, Begonias, and Fuchsias towards the end of the month.  Choose a well-drained spot with appropriate sunlight.
• Harden Off Tender Plants: If you've been growing tender plants indoors, gradually acclimatise them to outdoor conditions over a week or two by placing them in a sheltered spot for increasing periods each day.  This process, known as "hardening off," prevents shock.  Protect tender plants from late frosts (possibly to mid-May).
• Plant Out Potatoes: Earth up your potato plants as the shoots emerge to encourage more tuber development and protect them from frost.
• Plant Out Onion Sets and Shallots: Ensure your onion sets and shallots are planted in well-drained soil in a sunny location.
• Plant Out Corn: Sow corn seeds directly into the ground in blocks to aid pollination.
• Plant Out Climbing and Rambling Roses: Give these beauties a good start by planting them in well-prepared soil with support.
• Plant Out Summer Flowering Bulbs: Get your Gladioli, Freesia, and Eucomis bulbs in the ground for a spectacular summer display.
• Plant Out Dahlias: Once the risk of frost has passed, plant dahlia tubers in a sunny spot with rich, well-drained soil.  Provide support for taller varieties.
• Plant Out Tomatoes (Under Protection Initially): If you haven't already, plant out your tomato plants in a greenhouse, polytunnel, or a very sheltered spot.  They will need support as they grow.
• Plant Out Cucumbers (Under Protection): Similar to tomatoes, cucumbers thrive under protection initially.  Ensure they have something to climb on.
• Plant Out Peppers and Chillies (Under Protection): These heat-loving plants will benefit from the warmth and shelter of a greenhouse or polytunnel.
• Plant Out Aubergines (Under Protection): Aubergines also need warm conditions, so keep them under cover for now.
• Plant Out Courgettes and Squash: Plant these directly into well-manured soil in a sunny spot once the risk of frost has completely passed.

General Garden Care:

• Earth Up Potatoes: As mentioned above, continue to earth up potato stems as they grow.
• Pinch Out Side Shoots on Tomatoes: Regularly remove the side shoots that grow between the main stem and branches of cordon tomatoes to encourage better fruit production.
• Tie in Climbing Plants: As your climbing roses, clematis, and other climbers grow, tie them into their supports to keep them tidy and encourage upward growth.
• Start watering plants, preferably in the early morning or late evening.  Water deeply at the base of the plants.
• Keep on top of those weeds.  Tackle them while they are still small to prevent them from competing with your plants for water and nutrients.
• Feed Plants: Give established plants a boost with a balanced liquid feed to encourage healthy growth and flowering.
• Mulch Beds and Borders: Apply a layer of mulch (such as composted bark or well-rotted manure) around your plants to help retain moisture, suppress weeds, and improve soil structure.
• Protect Young Plants from Slugs and Snails: These pests can be particularly active in May.  Use your preferred method of control, such as barriers, traps, or organic slug pellets.
• Open greenhouse vents and doors on warm days to ensure good ventilation and prevent overheating.
• Deadhead Spring Flowers: Remove faded flowerheads from spring bulbs and other flowering plants to encourage more blooms or direct energy into bulb development.
• Prune Spring-Flowering Shrubs: Once they have finished flowering, prune spring-flowering shrubs like Forsythia and Ribes (flowering currant).
• Divide Overcrowded Perennials: May is a good time to divide overcrowded clumps of perennials like Geum, Hardy Geraniums, and Hellebores to create more plants and rejuvenate the original clump.
• Take Cuttings or Divide Plants: Now is the time to take cuttings or divide plants such as Penstemons, Bleeding Hearts, Cranesbills (Geraniums), Geum, Campanula, and Erysimum.

Keep an eye out for pests on plants.  Regularly inspect your plants for any signs of pests or diseases and take appropriate action promptly.

Specific Tasks:

• Sweet Peas: Keep sowing sweet pea seeds for a continuous display of fragrant flowers.  Provide support for climbing varieties.
• Lawns: Mow lawns weekly if you like them really neat, otherwise every other week so wildlife can enjoy your lawn and give wild flowers a chance to become established.  Consider feeding and treating for weeds if necessary.
• Hedges: Clip hedges if there are no signs of nesting birds.
• Spring Flowering Bulbs: Lift and divide overcrowded clumps of daffodils and other spring flowering bulbs once their foliage has started to die back.
• Penstemons: Once the last frosts have cleared it's time to cut back Penstemons, divide any congested roots and harvest shoots from the cut off branches.
• Buddleias: Once buddleias are leafing and the last frosts are over with, it's time to cut them back.  They are usually the last plant in your garden to start growing new leaves in spring.  Cut them back hard, to around knee height, if you want taller buddleia only take a small amount off top.  Cutting them back encourages new green growth that will produce more flowers.  By the end of April to the the middle of May my buddleia are attacked by aphids, the plants look half dead but I leave them alone and they always come back to life onces the aphids leave.
• Water Features: Clean out and restart your water features for the summer months.
• Vegetable Patches: Keep sowing salad crops and other quick-growing vegetables for a continuous harvest.  Thin out seedlings as needed.

May is a truly rewarding month in the garden, filled with the promise of the summer ahead.  By tackling these key tasks, you'll be well on your way to enjoying a beautiful and productive garden for months to come! Happy gardening!

More articles about wildlife gardening:

1.  How to attract birds to your garden
2.  How to attract bees to your garden
3.  Sowing and growing wildflowers