International Dawn Chorus Day is celebrated annually on 3 May. Visit the Wildlife Trust website to hear sound clips of the birds you may hear at this time of the year in the UK, including Robin, Blackbird, Song Thrush, Chiffchaff and more.
7 May marks the UN’s Day of the Full Moon (‘Vesak’): The Day of the Full Moon in the month of May, is the most sacred day to millions of Buddhists around the world. It was on the Day of Vesak two and a half millennia ago, in the year 623 B.C., that the Buddha was born. It was also on the Day of Vesak that the Buddha attained enlightenment, and it was on the Day of Vesak that the Buddha in his eightieth year passed away. (UN ‘Vesak Day‘)
The UN’s World Migratory Bird Day is celebrated on the second Saturday of May annually. In 2020 this was celebrated on Saturday 9 May. This global campaign is dedicated to raising awareness of migratory birds and the urgent need for international cooperation to conserve them.
20 May marks the UN’s World Bee Day This was adopted by the UN as a special day of international observance in 2017 to mark the importance of bees to overall human health and welfare.
On 22 May the world celebrates World Biodiversity Day.
Kitchen Garden
- Hand weed & hoe kitchen gardens regularly.
- Keep an eye out for early aphid and other pest attacks.
- Water newly planted trees & shrubs every 4 days (unless there’s prolonged rainfall)
- Thin vegetable seedlings that were direct-sown in April, including beetroot, spring onions and spinach.
- Broad Beans: Support with string attached to stakes 4 feet (1.2m) apart. Put in supports for pea plants & broad beans.
- Inspect gooseberry bushes regularly for signs of sawfly damage. Pick off by hand.
- Herbs: pinch out lemon balm and mint to prevent flowering and encourage bushy growth. Successional sowings of tender herbs such as basil can be made in May.
- Strawberries: Place straw under plants to keep fruit clean; straw mulch also helps discourage slugs and snails. Feed plants with tomato fertiliser every week or two.
- Start earthing-up potatoes when foliage shoots reach 9 inches (23 cm) to prevent green tubers and remove any cold-damaged leaves.
- Remove raspberry suckers encroaching on paths or between rows.
Indoors
- Beans: Frost-tender French and runner beans can be sown indoors individually into 3 inch pots. Plant out early next month.
- Brassicas like Cauliflower, Savoy cabbage, purple sprouting broccoli, kale and calvero nero all need a long growing season. Start seedlings now in small pots and transplant when sturdy with 4 or 5 sets of leaves.
Plant-out tender vegetables — after all risk of frost has passed
- Tomatoes – hold back from planting outdoors too early. Tomatoes suffer if exposed to temperatures below 12 C.
- Courgettes – towards the end of May. Harden-off plants under cloches to protect against frosts.
- Pumpkins – towards the end of May.
Sow Directly into prepared ground
- Succession sow borage from May to July.
- Succession sow herbs such as basil, coriander, dill & parsley every 10-14 days
- Succession sow salad crops.
- Sow carrots, radishes, beetroot, lettuce and spring onions successionally for continuous cropping
- If weather is favourable in milder regions sow French & runner beans directly into soil in late May.
- Sow cauliflower, sprouting broccoli and leeks for harvesting next winter.
- Sow parsnip now in the position they are to crop to give small roots for winter.
Harvest
- Start harvesting asparagus from established plants when spears are 5-7 inches tall (13-18cm), cutting 1 inch below soil level.
- Chives & garlic chives can be trimmed to add to salads and egg dishes.
- Harvest early crops of radish & salad leaves as they mature (and continue sowing for succession crops).
- Rhubarb. Harvest up to half the stems of established rhubarb clumps (don’t take more than half the stalks).
- Strawberries can be harvested as they ripen.
Flower / Ornamental Garden
- Prune overgrown camelias as they start to put on fresh growth. Cut to young sideshoots which will flower next year.
- Prune spring-flowering clematis such as evergreen clematis montana after flowering to control growth.
- If daffodil flowering was poor, lift and divide bulbs. Replant larger bulbs in ground improved with organic matter. Continue dead-heading spring flowering bulbs. Let foliage die down before cutting (or lifting).
- Bearded Iris come into flower in early May.

Iris on the back patch, Early May 2019.
- By early May the lilac are in bloom – fragrant and abundant. Always makes me dream of Chagall’s lyrical donkeys and flying lovers and fiddler players. Lilac are the flower of young love. Of the tides of spring. Of the surge of life in all it’s ferocity.
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Lungwort, late May 2020.
Cut back lungwort (pulmonaria) spent flower stalks and leaves to promote healthy new growth and minimise powdery mildew.
- Peony buds emerge and explode like floral fireworks in May. The blossoms are richly exuberant. Peony have short-lived blooms, but are spectacular for as long as they last. Early May is the time to get supports in.
- Stake, support and tie-in perennials with tall flower stems such as delphinium or plants with heavy, large blooms (like peonies). Foxglove (Digitalis) also like staking.
- Prune spring-flowering shrubs such as Forsythia and Philadelphus (mock orange).
- Lily (especially Asiatic Lily): look out for lily beetle adults & larvae – early control helps to keep populations low.
- Clip evergreen hedges like the pyrocanthus (but check for nesting birds first)
- Prune hardy perennials (‘Chelsea chop’) – sedums, daisies, chrysanthemums, etc
- Tie-in wayward sweet pea shoots to supports.
Planting
- Finish planting summer bulbs – eg crocosmia, gladioli, lilies.
- Tender summer bedding (eg lobelia) should be thoroughly hardened off before planting. A cold frame open during the day and closed at night, is ideal.
- Plant out tender exotics such as cannas and dahlias after all risk of frost has passed. Make sure you apply slug & snail controls to dahlias as they put on new growth.
- A sowing of Cosmos in late May will give you blooms from August onwards.
- Thin direct-sown hardy annuals such as California poppy.
- Tie-in sweet peas to their supports.
Cuttings & Propagation
- Detach baby rosettes from succulents such as echeveria and pot into small containers of gritty compost.
- Take softwood cuttings of hardy and tender perennials like fucschias and verbena.
Wild Things
- May is the start of moth-flight season for many UK species. Night-scented plants (honeysuckle, jasmine, evening primrose etc) attract moths, which in turn attract bats.
- Check for nesting birds nests in hedges and shrubs.
- Watch for bats at dusk.
- Summer migrant birds such as swifts, swallows and martins arrive to the UK in April and May, having wintered in Africa.