Allowing a patch of grass to grow long helps butterflies

Letting parts of your garden go wild with long grass boosts butterflies – particularly in towns and intensively farmed areas, a study has found.

Research from wildlife charity Butterfly Conservation analysing butterfly sightings from more than 600 gardens around Britain found a small but significant increase in butterfly numbers and species in gardens with a patch of long grass.

The study found a boost to wildlife is likely to be biggest in highly arable areas, where gardens with long grass could see up to 93% more butterflies, while those in urban areas with long grass could boost numbers by up to 18%.

The Butterfly Conservation scientists behind the report said it proved for the first time that letting a patch of garden grass grow long could help the insects.

Private gardens make up 728,000 hectares (nearly 1.8 million acres) of land across Great Britain.

So while the increase in butterfly numbers in each garden was small, letting a patch in many gardens across the country go wild could make a huge difference to butterflies species, many of which are in decline.

The analysis showed increases in species which feed or breed in grass – such as gatekeepers, meadow browns, speckled wood and large and small skipper butterflies – suggesting long grass could provide habitat to help boost populations.

Dr Richard Fox, head of science at Butterfly Conservation and coauthor of the study, said:“The benefits of each individual wild space are small, but if thousands of people get involved the boost to butterflies could be huge.”