Sir David Attenborough is urging people to plant butterfly-friendly flowers in their garden to help reverse declining numbers of the insects.
The nature legend made the call as he launched the annual Big Butterfly Count, in which people are asked to spot and record 18 species of common butterflies and two day-flying moths over three weeks of the summer.
The world's largest butterfly survey aims to find out how common butterfly species are doing and how to protect them in the future.
People are also being asked to look out for painted ladies, with the biggest immigration of the butterfly into the UK since 2009, when millions came over from the continent.
Sir David, who is Butterfly Conservation president, said everyone could play a part in reversing declines in butterflies, insects and other wildlife.
Gardeners should plant pots in their gardens or window ledges with nectar sources such as catmint, lavender, cranesbill, oregano and Echinacea, he urged.
The plants would provide food needed by butterflies, moths, bees and other pollinating insects and attract species such as red admirals, brimstone and green-veined whites.