Warm, sheltered sites for overwintering are vital for a butterfly's survival

 This is equally true whether they overwinter as eggs, caterpillars, chrysalises or adult butterflies.

An obsession with tidyness results in the destruction of these sites.
Butterflies NEED old trees, undisturbed clumps of dead vegetation and derelict outbuildings to survive the British winter.

CREVICES IN THE BARK OF OLD TREES

Old trees like this Oak are best as they have more cracks and crevices than young saplings. Don't allow them to be cut down.

IVY-CLAD WALLS

A thick coating of ivy and other climbers provides not only winter shelter, but nectar in spring, and berries for birds in winter.
No idyllic country cottage, then a boundary wall or old shed will do.

THICK CLUMPS OF  VEGETATION

A good thick tuft of grass or any  sizeable wildflower can provide winter refuge for insects, but only if it is not mowed to the ground.

EVEN A DILAPIDATED OUTHOUSE

In the absence of more natural alternatives a dilapidated outhouse can provide a good alternative, especially for hibernating adult butterflies like the Peacock and Small Tortoiseshell.
Avoid the temptation to demolish it, cover it will ivy or climbing roses instead.

A woodland habitat with flowers for nectar, caterpillar food plants, and hibernation sites