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

You've planted the buddleia, the lavender, maybe a patch of verbena, and the usual crowd shows up: whites, a red admiral, a peacock if you're lucky. But some butterflies never come near the garden at all, even when you live well within their known range. That's not bad luck or bad planting. For a handful of Scotland's rarer species, the reason is closer to biology than horticulture: what draws them isn't nectar, it's a specific plant their caterpillars can eat, and often a very specific type of ground it has to be growing in.

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 own species list for garden butterflies is entirely common ones: red admiral, peacock, brimstone, painted lady, comma, the whites, orange-tip, speckled wood, meadow brown, small copper, holly blue, common blue. Scotch Argus, Chequered Skipper and Small Blue appear nowhere on it, and its foodplant list for those common species, grasses, birds'-foot trefoil, nettle, buckthorn, docks, garlic mustard, thistles, holly and ivy, doesn't include the two plants that actually matter here: purple moor-grass and kidney vetch. Buddleia and lavender feed adult butterflies passing through; they don't feed a single caterpillar of any of the three species covered here.

Telling them apart

Scotch Argus is a mid-sized dark brown butterfly with orange-ringed black eyespots on both wings, on the wing later in summer than almost anything else you'll see, if you spot a dark brown "meadow brown-type" butterfly in a boggy upland field in August, in the west or north of Scotland, that's a reasonable candidate. Chequered Skipper is small, fast, and darts low over grass rather than gliding, its chequered orange-and-brown wing pattern is distinctive at rest, but its size and flight style mean it's easily mistaken for a moth in the first instant. Small Blue is genuinely tiny, the UK's smallest resident butterfly, at 2 to 3cm wingspan, and dull sooty-brown-blue rather than the bright blue of a common blue; scale and colour together are the giveaway. None of this is a substitute for a proper field guide, but it's worth knowing before assuming a fast-moving brown blur couldn't possibly be one of these three.

Two labels come up throughout, worth explaining once: the GB Red List is the official extinction-risk classification for Great Britain, categories like Vulnerable, Near Threatened, and Least Concern, the same style of ranking used for the IUCN's global Red List, just scoped to GB. Butterfly Conservation priority is the charity's own internal 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 Butterfly Conservation judges its efforts are most needed.

Scotch Argus

Butterfly Conservation describes it as common and widespread in much of western and northern Scotland, though it has declined in the southern part of its range, especially in England, where it's reduced to just two isolated sites. It favours damp, acid or neutral grassland up to 500m in montane regions of Scotland, and around the fringes of sheltered bogs, in woodland clearings, and young plantations, tall grassland, lightly grazed or ungrazed.

The main foodplant in Scotland is thought to be purple moor-grass, though there are few observations from Britain and other grasses may be used. Flight season runs later in summer than most UK butterflies, typically mid-July into August.

Its GB Red List status (2022) is Vulnerable, with a Butterfly Conservation priority of Low, and it's classed as Near Threatened across Europe. Abundance has actually risen 76% between 1979 and 2019, even as its distribution has shrunk 20% since 1991, more individuals where it persists, but retreating from some areas.

Butterfly Conservation publishes no garden-relevant advice for this species at all. It's a species of open hill and bog-edge grassland, often at altitude, not garden borders. If you already have the right damp, tall, lightly grazed or ungrazed grassland with purple moor-grass, and are in an area where it's established, leaving it uncut is the one action grounded in what's known, but nothing suggests a typical garden could support it from scratch.

Chequered Skipper

It's known to be found within roughly 30 miles of Fort William, with strongholds 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. England's Rockingham Forest population is a separate 2018-19 reintroduction from continental stock, following the species' 1976 English extinction; Scotland's is the original surviving stronghold.

Its foodplant is purple moor-grass, the same as Scotch Argus in Scotland, and its flight season runs mid-May to the end of June. It's legally protected under the Nature Conservation (Scotland) Act 2004. Its GB Red List status is Least Concern, but its Butterfly Conservation priority is High, and it's genuinely expanding: distribution is up 66% between 2000 and 2019, with new records on Skye and Mull attributed to climate-linked early warm springs.

That expansion is real, but it's happening at moorland and woodland-clearing scale across the west Highlands, not in garden beds. If you have genuinely suitable rough, damp, woodland-edge grassland within or near its range, growing purple moor-grass and leaving it uncut aligns with its needs; a lawn or border doesn't.

Small Blue

This one isn't a Scottish stronghold species the way the other two are; its main population core is south-central England, and Scotland holds scattered, declining coastal remnants instead. Its Scottish story is a rescue effort, not a stronghold. It's been lost from Scotland's west coast, holding on in the east, with current focus areas in Angus, Berwickshire, Moray, and Aberdeenshire, in sheltered, warm grassland with kidney vetch: coastal grassland, dunes, quarries, and disused railways.

Its sole foodplant is kidney vetch; the larvae live only in the flower heads. Flight season is typically May to June in Scotland, with an occasional second brood in exceptional years, not the norm. Its GB Red List status is Near Threatened, with a Medium Butterfly Conservation priority, and the numbers tell a harder story than the other two: national distribution is down 43% since 1983, and Scottish abundance is down 39% since 2005.

Butterfly Conservation is direct about the limits here: the Small Blue lives in wild, uncultivated places, is often reluctant to stray far from its origin, can easily be overlooked, and doesn't come into gardens, so people simply don't see it much. This isn't a plant-it-and-it-will-come species.

But 2025 brought a genuinely good story. A volunteer counted 523 Small Blues at Balnagown Estate near Invergordon, double the prior year's count, plus new colonies at Wick and Nairn Railway Station, and rising counts at several named sites, through Species on the Edge, a partnership between NatureScot and seven charities funded by the National Lottery Heritage Fund.

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

What's realistically actionable for a gardener

Range and habitat type come before planting choice, outside the right range or habitat, no amount of the right plant substitutes for the right ground. Don't mow what you don't have to: there's no published safe cutting window for suspected habitat, so the cautious approach is to avoid cutting it at all rather than guess a timing. A garden alone rarely creates a colony even under close-to-ideal conditions, a documented Cumbria reintroduction of Small Blue saw only single-figure sightings for three years even with kidney vetch already established and an expert-led release, only breaking out in year four. Connecting with an existing project, Species on the Edge or a local Butterfly Conservation branch, achieves far more than acting alone, and recording any sightings through iRecord Butterflies or a local branch feeds directly into the same conservation effort. Patience here is measured in years, not one season.

Common questions

Sources