Your May wildlife gardening jobs

But May’s abundance is only a fraction of what it was. Bird, mammal, reptile and amphibian populations have decreased sharply in recent decades, as have the invertebrates upon which many animals feed. Vital habitats like woodlands, wetlands and heathlands are still being destroyed and intensive agriculture continues to affect biodiversity. With around a million acres of gardens across the UK, our choices make a big difference. This month is an ideal time to develop habitats that support insects, and then enjoy the wildlife they attract to our gardens.

More wildlife advice:

• How to help garden wildlife in May

Plants for wildlife

For spectacular nectar-rich displays this summer, plant out half-hardy annuals that were sown earlier in spring. Harden plants off over a couple of weeks before transplanting into the garden after the last frost. We love black-eyed Susan (Rudbeckia hirta) which is often grown as an annual, although it can survive for a few years in mild, sheltered areas.

These North American prairie plants have richly-coloured flowers and, as members of the daisy family, are loved by pollinating insects as much as they are by gardeners. ‘Indian Summer’ has large butter-yellow blooms with characteristic dark centres and ‘Cherry Brandy’ adds drama to any border with its glorious deep red-maroon flowers that last well into autumn. For more compact plants, try growing sunny ‘Toto’. This floriferous yellow star reaches around 30cm in height and is perfect for containers and the front of sunny borders.

Don’t worry if you haven’t sown any seeds yet, it’s not too late to add half-hardy annuals to the borders. Many species, such as Cosmos bipinnatus and Phlox drummondii, are resilient enough to be sown outside towards the end of this month, or they can be purchased as plug plants ready to go in the garden.

• How to grow rudbeckias
• How to harden off plants

Feeding wildlife

May is a busy month for blue tits and great tits. Most eggs hatch in the next few weeks and adults can have up to 16 hungry mouths to feed, though 8-10 is more usual. In spring and summer, adult tits eat invertebrates, especially spiders and caterpillars, and the young are primarily fed on caterpillars. A study by the University of Glasgow in 2017 showed that blue tits in urban habitats raised fewer young than birds in rural areas, due to the scarcity of caterpillars. Each nestling needs around 100 caterpillars a day to thrive, so parents need to forage for nearly 1,000 caterpillars every day to feed an average brood.

Many trees and shrubs provide excellent habitats for butterfly and moth caterpillars, so they benefit the birds too. Willow, birch and oak trees, and hedges with hawthorn, blackthorn, spindle and privet create fantastic food sources for a wide range of moth caterpillars. Fruit trees and bushes, along with climbers like native honeysuckle (Lonicera periclymenum) and ivy (Hedera helix), provide food for both larval and adult stages.

The brimstone moth (Gonepteryx rhamni) is one of my favourite spring moths. It has brown notched patterns on its pale-yellow wings and its caterpillars feed on hawthorn, blackthorn and rowan. It is attracted to light, which explains why we sometimes find them on the inside of our open windows. Grasses also support many butterfly and moth larvae, such as those of the marbled white (Melanargia galanthea), gatekeeper (Pyronia tithonus) and the drinker moth (Euthrix potatoria). Creating an area of your garden where native grasses can grow will help provide food for these wonderful creatures.

• Caterpillar food plants

Bats

Thriving moth populations are also likely to attract hungry bats. All 17 of the UK’s breeding bat species feed on insects such as moths, midges and lacewings, so a garden that caters for them will also provide a banquet for bats. Ponds and areas of long grass create brilliant habitats for larvae, and avoiding pesticide use also enables insect populations to thrive. Growing different types of flowers helps broaden the range of insect species that visit your garden, and night-scented blooms, such as evening primrose and sweet rocket, are particularly attractive to moths.

Artificial light sources like decorative garden lighting and security lights can have a detrimental effect on both bats and moths, so avoid lighting wherever possible. If you would like to get more involved with bats in your area, you can find out about local groups from the Bat Conservation Trust.

Creating and maintaining habitats

Pond plants

Pond plants come into active growth as spring temperatures increase, so this month is a good time to plant and divide aquatic perennials. Adding a range of wildlife-friendly plants that grow naturally in UK waterways helps support a diverse ecosystem, from tiny larvae up to larger visitors like grey wagtails and grass snakes. Submerged foliage provides tadpoles and other aquatic creatures with protection from predators and shade in hot weather. Underwater plants also maintain the oxygen supply in the water ensuring an aerated, healthy environment for wildlife.

Spiked water-milfoil (Myriophyllum spicatum) provides a place for pond creatures like water beetles to hide and fronds upon which damselflies and dragonflies can lay their eggs. We have rigid hornwort (Ceratophyllum demersum) in our small wildlife pond. Its feathery foliage forms dense clumps that are great for sheltering larvae and tadpoles. Floating plants such as frogbit (Hydrocharis morsus-ranae) and common water crowfoot (Ranunculus aquatilis) also create shade and places for pond animals to lay their eggs.

Adding flowering marginal plants like water mint (Mentha aquatica), kingcups (Caltha palustris) and water forget-me-not (Myosotis scorpioides) provides pollen and nectar for bees, hoverflies and butterflies. Kingcups have yellow buttercup-like flowers on tall stems between April and June. Later in the season, the stems are used by dragonfly nymphs climbing out of the water to complete metamorphosis into newly-emerged adults or tenerals. As well as being good for pollinators, water mint and water forget-me-not are favoured by newts, which lay eggs on them, wrapping each individual one in a folded leaf.

• British native pond plants for wildlife ponds
• How to repot pond plants in spring

Look out for... warblers

By early May, most migratory warblers are back for the new breeding season. Some species such as whitethroats will have travelled from Africa, while other warblers like blackcaps have just completed a shorter journey from the Mediterranean. Now that resident birds like robins, wrens and blackbirds are joined by the warblers, mornings open with a delightful symphony of territorial song. National Dawn Chorus Day takes place on 7 May this year, so why not catch up with one of the events taking place all around the UK, and join many others enjoying this inimitable celebration of spring?

• The first chiffchaff of the season singing its own name ‘chiffchaff chiffchaff’ never fails to excite me. I generally expect to hear the characteristic call around the middle of March, but more recently it is thought that around 1,000 chiffchaffs have been overwintering in the UK rather than migrating to Europe or North Africa. This slender, olive-green warbler breeds in scrub and woodland, making domed nests near or on the ground in thick vegetation. They visit gardens to feed on invertebrates – we sometimes spot them flitting around in the silver birch picking tiny insects off the newly-emerged leaves.
• Willow warblers arrive in the UK from Africa in early April. Looking very similar to the chiffchaff, this warbler can be identified most easily by its song, which comprises a series of descending notes. Willow warblers have pale pink legs (as opposed to chiffchaffs’ dark brown legs) and are usually brighter with more yellow in the plumage. They are birds of open woodland, but can also be heard singing in scrubland, parks and even – if you are extremely lucky – in large gardens. Like chiffchaffs, they build a dome-shaped nest near the ground and lay between five and seven white eggs with reddish-brown speckles.
• Much easier to identify with its black (or in the female’s case reddish-brown) cap, the blackcap is an attractive warbler that primarily feeds on insects. Unlike chiffchaffs and willow warblers, blackcaps nest in shrubs and trees, so they will breed in gardens with plenty of shrubby cover, as well as in woodland and parks. Although many blackcaps now overwinter in the UK, these birds will likely have left for their breeding grounds in central Europe, especially southern Germany, by now. The blackcaps we hear singing their glorious lilting melodies in spring have migrated here from southern Europe or north Africa, arriving around the middle of April.
• You would think that garden warblers would be one of the easiest birds to spot in our gardens in spring, but their name is rather a misnomer. This shy warbler nests in woodland and scrub, but rarely visits gardens unless they have large areas of dense shrubbery and tree cover. If you do see a garden warbler, its most notable feature is its anonymity. It has plain, grey-brown plumage and a song easily confused with the blackcap’s melodic warbling.