Why colour only gets you so far

Colour is the quickest way into a butterfly identification, but on its own it will mislead you. A red admiral, a small tortoiseshell and a comma all read as "orange with dark markings" when one is moving fast across a flowerbed. Use colour as a first filter, then confirm the species with wing pattern, date and habitat. Wing pattern is the deciding evidence; colour just narrows the field.

Notice whether the butterfly is holding its wings open or closed, because the underside often carries a completely different set of markings. A peacock basking with wings spread looks nothing like the same insect with wings folded into a dark, leaf-like shape with a pale edge. Jot down the date and the place — a few seconds of detail now saves a lot of head-scratching later.

The orange and red group: red admiral, peacock, comma and small tortoiseshell

These four cause most garden confusion, and all of them rely on stinging nettles for their caterpillars. Look closely and each has a signature.

• Red admiral — velvety black wings crossed by bold orange-red bands, with white spots near the wingtips. The underside is dark, mottled brown and hides it beautifully against bark. It rarely basks with wings open for long, feeding instead on ivy flowers in autumn.
• Peacock — deep red upper wings with four large eyespots ringed in yellow, blue and black. Nothing else in a British garden looks like it. The underside is almost black, the form you see in hibernation.
• Small tortoiseshell — smaller and more orange, with black and cream patches and a row of blue spots around the wing margins. It often basks with wings spread on warm gravel or bare ground.
• Comma — ragged, jagged wing edges, orange with dark spots, and a white comma-shaped mark on the dark underside. That ragged outline is the giveaway, even in flight.

Painted ladies are also orange and arrive in some years in large numbers. They are a stronger salmon-pink with black wingtips dotted white, and they do not hibernate here.

Whites, brimstones and orange-tips

White butterflies get dismissed as "cabbage whites", but there are several to tell apart. The large white is big and bold, with heavy black wingtips; the female has two black spots on each forewing. The small white is daintier, with greyer, softer tips. The green-veined white shows delicate greenish veins along the underside, best seen when it rests with wings closed.

The brimstone looks like a fluttering pale leaf — lemon-yellow in males, greenish-white in females — and it is usually the first butterfly of the year, often on the wing by March. The orange-tip flies from April to June; males have vivid orange wingtips with a black edge, while females lack the orange and must be separated from small whites by the green mottling on the hindwing underside.

Browns and blues: the quieter visitors

Brown butterflies rarely sit on flowers, so you often spot them fluttering through long grass instead. The speckled wood is chocolate-brown with creamy spots and loves dappled shade at the edge of trees and hedges. The meadow brown is a soft brown with orange patches and one small eye-spot on each forewing. The ringlet is darker still, almost velvety black when fresh, with small ringed spots. The gatekeeper is more orange, with brown borders and a double eye-spot, favouring sunny, sheltered patches of long grass.

Blues need a closer look. The holly blue is the one you are most likely to see in a garden, flitting around holly in spring and ivy later in summer, silvery-blue with a pale greyish underside. The common blue is brighter, with orange spots along the hindwing edge underneath. Both are small and restless, so watch where they land rather than trying to follow them in the air.

Flight times and habitat clues

The date you see a butterfly can be as useful as its colour. As a rough calendar, expect:

• March–April: brimstone, comma, peacock and small tortoiseshell emerging from hibernation.
• May–June: orange-tip, green-veined white, holly blue, common blue and speckled wood, with the first meadow browns.
• July–August: the peak — meadow brown, ringlet, gatekeeper, large and small whites, and the first red admirals and painted ladies.
• September–October: red admirals at their most numerous, feeding heavily on ivy and sedum before winter.
• Mild winter days: a red admiral may take to the air, and a brimstone or peacock can briefly wake from hibernation.

Habitat narrows things further. Nettles mean red admiral, peacock, small tortoiseshell or comma. Long, uncut grass points to meadow brown, ringlet or gatekeeper. Holly and ivy suggest holly blue. Any brassica or nasturtium is likely to host large or small whites.

A few plants that bring them close enough to check

Identification gets much easier when the butterfly is nectaring a metre away rather than hurtling past. Buddleia earns its reputation, but native plants work just as hard and support caterpillars too. Try hemp-agrimony, marjoram, field scabious, ox-eye daisy, knapweed and birdsfoot trefoil in a sunny, sheltered border. Let a patch of ivy flower in autumn, when red admirals and commas depend on it.

Above all, leave a sunny corner of nettles to grow through the summer — not the tidy patch behind the shed, but a real clump in the open. Cut it back in rotation so there is always fresh growth, and you will have red admirals, peacocks, commas and small tortoiseshells breeding in the garden rather than merely visiting. The more time they spend with you, the better you will get at telling them apart.