Five weird and wonderful types of beetles to nurture

BEETLES may not be as pretty as butterflies or as buzzy as bees but they play a vital role in every healthy garden, according to the Royal Horticultural Society (RHS) and the Wildlife Trusts, which are calling on gardeners to help these creatures for this year’s Wild About Gardens campaign.

With more than 4,000 beetle species in the UK, including ladybirds, ground beetles and rose chafers, gardeners need to provide a patch for them to encourage balance in the garden and boost biodiversity, say campaigners.

Helen Bostock, RHS senior horticultural adviser and wildlife gardening expert, says: “Beetles were perhaps the first ever insect pollinator, being around in the age of the dinosaur and around a quarter of Britain’s beetles are thought to be involved in pollination.”

Here she picks five favourite beetles and explains what gardeners can do to support them.

DEVIL’S COACH HORSE BEETLE

If you stumble across a devil’s coach horse, bottom right, you could be forgiven for thinking you have just had an encounter with a small black scorpion.

This is due to its defensive reaction of arching its tail up over its head. It can also exude a distinctive odour when threatened.

Although there is no sting in the tail, don’t be fooled into thinking it is a softy. Emerging after dark, this fast and ferocious beetle hunts many other invertebrates and can give a human a painful nip if handled.

Rove beetles, of which the devil’s coach horse is Britain’s biggest, are predatory, notable for their short wing cases and long bodies. Many are black but some sport red wing cases, others are multi-coloured including blues and there are species that have yellow hairs.

The smallest species of rove beetle are less than 1mm long, but the devil’s coach horse is a heavyweight, at 3cm long.

Action: Put out piles of stones for daytime cover.

SEVEN-SPOT LADYBIRD

Most will be familiar with ladybirds, left, including this distinctive native species with its seven black spots, but not everyone will know that they are beetles.

Their shiny rounded shell is in fact a pair of protective wing cases (known as elytra and common to nearly all beetles) which open when the ladybird flies to reveal a membranous second pair of wings below.

A ladybird has a huge appetite, munching about 5,000 aphids (greenfly and blackfly) in its yearlong life. Both larvae and adults are predatory, helping gardeners keep down populations of aphids.

As with other native ladybirds, the seven-spot is under pressure from the non-native harlequin ladybird.

Action: Avoid sprays which could harm ladybirds.

ROSE CHAFER

Chafers can get a bad press. While Welsh and garden chafers can be to blame for damaged lawns, and summer chafers and cockchafers nibble a few plant roots in borders, other chafers carry out different functions in gardens.

The rose chafer is a rather fetching beetle. The adults, up to 2cm long, are copper-green with distinctive white flecks. Spot them in flowers such as roses and hogweed. Admittedly, they do feed as an adult on flowers and leaves but not to any major extent.

Their creamy-white grubs can be found in compost heaps, feeding on rotting vegetation, helping to recycle plant nutrients. Elsewhere they feed on rotting leaves in hedge bases. Action: Build a compost heap if you don’t already have one.

SEXTON BEETLE

Sexton beetles offer an undertaker service for the corpses of small rodents and birds. The carcass acts as a “first date” venue for males and females who can detect it with receptors in their antennae as quickly as an hour after death and from up to two miles away.

The pair can drag the corpse to suitable soft ground if required for they will begin to bury it in a shallow chamber. After mating, the female lays her eggs on the corpse. This species is highly developed and the parent beetles stay on to care for the larvae.

The adults are chunky, up to 3cm long with black bodies strongly marked with irregular orange bands. Action: Allow sexton beetles time to undertake their work if you stumble across a dead mouse or bird in your border.

THICK-LEGGED FLOWER BEETLE

Often found on the flowers of daisies and brambles, this is a bright green metallic beetle, main picture, which is up to 11mm long. Occasionaly found in Scotland, only the males sport the wondrously swollen thunder thighs from which it takes its name.

The larval stage feed in thistle stems, while the adults feed on pollen (not enough to cause damage) and nectar.

Action: Plant plenty of flowers to support them such as ox-eye daisy, buttercup and hardy geranium.

More campaign information can be found at wildaboutgardens.org.uk.