Rare Scottish Butterflies: What Home Gardeners Can (and Can't) Do

A garden can't do much for Scotland's rarer butterflies, because what draws them isn't nectar but a specific plant their caterpillars eat, growing in a specific type of ground. Scotch Argus and Chequered Skipper both depend on purple moor-grass in damp, tall, lightly grazed or ungrazed grassland, and the Small Blue depends on kidney vetch on sheltered, warm coastal ground. Buddleia and lavender feed passing adults but not one caterpillar of the three. The best things a gardener can do are leave suitable rough ground uncut, record sightings, and join an existing project rather than planting speculatively.

The Scotch Argus, the Chequered Skipper and the Small Blue show this clearly. Each is tied to Scotland in a different way and to a different degree, and each has real limits on what a garden, however well planted, can do for it.

Why the usual butterfly-garden advice misses these three

The RHS's garden-butterfly advice covers common species such as red admiral, peacock, brimstone, painted lady, comma, small tortoiseshell and the whites. Its foodplant list (nettle, brassicasThe cabbage family: cabbage, kale, broccoli, cauliflower, Brussels sprouts, kohlrabi, swede, turnip and more, sharing the same pests, diseases and rotation rules. Full definition →, docks, thistles, birds'-foot trefoil, holly and ivy, mixed meadow grasses and so on) doesn't include the two plants that matter here: purple moor-grass and kidney vetch. Scotch Argus, Chequered Skipper and Small Blue aren't on it.

Telling them apart

Scotch Argus is a mid-sized, dark brown butterfly (wingspan 35 to 40mm) with orange-ringed black eyespots, on the wing later in summer than almost anything else. A dark brown "meadow brown-type" butterfly in a boggy upland field in August, in the west or north of Scotland, is a reasonable candidate. Males fly low through the grass almost constantly in sun, while females bask on grass clumps. Chequered Skipper is small and fast and darts low over grass rather than gliding; its chequered orange-and-brown pattern is distinctive at rest, but its size and flight mean it is easily mistaken for a moth. Small Blue is tiny, the UK's smallest resident butterfly at 2 to 3cm wingspan, and a dull blue-grey to brown rather than the bright blue of a common blue. Scale and colour together give it away. None of this replaces a proper field guide.

Two labels recur below. The GB Red List is the official extinction-risk classification for Great Britain, with categories such as Vulnerable, Near Threatened and Least Concern. Butterfly Conservation priority is the charity's own ranking (Low, Medium or High) of which species most need conservation attention and funding. A High priority species isn't necessarily rarer than a Low one; it reflects where the charity judges its effort is most needed.

Scotch Argus

The Scotch Argus is common and widespread in much of western and northern Scotland, though it has declined at the southern edge of its range and survives at just two isolated sites in England. It favours damp, acid or neutral grassland up to 500m, and also bog fringes, woodland clearings and young plantations, in tall grassland that is lightly grazed or ungrazed. Its main Scottish foodplant is thought to be purple moor-grass, though other grasses may be used. It flies later in summer than most UK butterflies, typically from mid-July into August.

Its GB Red List status (2022) is Vulnerable, with a Butterfly Conservation priority of Low, and it is Near Threatened across Europe. Abundance rose 76% between 1979 and 2019, even as distribution shrank 20% from 1991: more individuals where it persists, but retreating from some areas. If you already have damp, tall, lightly grazed or ungrazed grassland with purple moor-grass in an area where it is established, leaving it uncut is the one action grounded in what's known. Nothing suggests a typical garden could support it from scratch.

Chequered Skipper

The Scottish stronghold is within roughly 30 miles of Fort William, with important populations at Allt Mhuic, Glasdrum Wood and Ariundle Oakwood. Its habitat is damp hollows, sheltered south-facing slopes and tall purple moor-grass at the edge of open broadleaved woodland or low scrub. It died out in England in 1976, and England's Rockingham Forest population is a reintroduction; Scotland's is the original surviving stronghold. Its foodplant in Scotland is purple moor-grass, and it flies from mid-May to the end of June.

It is legally protected in Scotland under the Nature Conservation (Scotland) Act 2004. Its GB Red List status is Least Concern, but its Butterfly Conservation priority is High, and it is expanding: distribution is up 66% between 2000 and 2019, with records reaching Mull (2021), Loch Awe and Skye (2025), which experts attribute to climate, including early, warm springs. That expansion is happening at moorland and woodland-clearing scale across the west Highlands, not in garden beds. If you have suitable rough, damp, woodland-edge grassland within or near its range, leaving existing purple moor-grass uncut fits its needs; a lawn or border doesn't. A garden bordering the right kind of ground could end up next to a new colony over time, though nothing you plant will summon one.

Small Blue

This isn't a Scottish stronghold species like the other two. Its main population core is in south-central England, and Scotland holds scattered, declining coastal remnants. It has been lost from Scotland's west coast and holds on in the east, with current focus in Angus, Berwickshire, Moray and Aberdeenshire, on sheltered, warm grassland with kidney vetch: coastal grassland, dunes, quarries and disused inland railway lines.

Its only foodplant is kidney vetch, and the larvae live only in the flower heads. In Scotland it typically flies in May to June, and a second brood can occur in good years. Its GB Red List status is Near Threatened, with a Medium Butterfly Conservation priority, and the trends are harder than for the other two: national distribution is down 43% from 1983, and Scottish abundance is down 39% since 2005. Kidney vetch isn't on the RHS garden foodplant list, and the butterfly lives in wild, uncultivated places, is reluctant to stray far from where it already lives, is easily overlooked and doesn't come into gardens, so people rarely see it. This isn't a plant-it-and-it-will-come species.

But 2025 brought good news. At Balnagown Estate near Invergordon a volunteer counted 523 Small Blues in 90 minutes on 21 May, double the previous year's count, and new colonies turned up near Wick and at Nairn Railway Station, after a warm spring. Habitat work through Species on the Edge, a partnership including NatureScot and charities supported by the National Lottery Heritage Fund (scrub removal and kidney vetch restoration at coastal sites), is credited with helping.

At Ardersier Primary School, pupils grew kidney vetch that volunteers then planted into new "butterfly banks" nearby. That is a rare small-scale action that worked, because it was coordinated with an established project rather than attempted alone.

What a gardener can realistically do

Range and habitat come before planting choice. Outside the right range or ground, no plant substitutes for the right habitat. Don't cut suspected habitat unless you have to; there's no known safe cutting window, so the cautious approach is to avoid cutting it at all. A garden alone rarely creates a colony even in close-to-ideal conditions. In a Small Blue release in north-east England, using butterflies taken from a Cumbrian colony, counts stayed in single figures from 2020 to 2022 and the breakthrough came in 2023. Connecting with an existing project, Species on the Edge or a local Butterfly Conservation branch, achieves far more than acting alone, and recording sightings through iRecord Butterflies or a local branch feeds the same effort. Patience here is measured in years, not one season.

Common questions

Sources