Thalictrum alpinum aka Arctic Meadow Rue

Thalictrum alpinum, or alpine meadow rue, is a small herbaceous perennial. It belongs to the buttercup family, Ranunculaceae. Its native range spans subarctic and subalpine parts of the Northern Hemisphere. It is native to Britain and Ireland. These habitats place it among plants of cool northern and mountain regions. The RHS also lists Thalictrum microphyllum as a synonym.

This plant forms a compact clump with a leafy mound. Garden plants reach about 0.3–1.6 feet (0.1–0.5 metres) tall and wide. They take two to five years to reach full size. The leaves have a blue-green hue and a divided shape. Each small leaflet has three lobes. Leaflets reach about 0.03 feet (0.01 metres) across. The foliage is deciduous, so the plant does not keep its leaves year-round.

Short stems carry clusters of small flowers above the leaves. Bloom comes in late spring and early summer. Each flower has a bell-shaped calyx made of green-purple sepals. Within it sit purple stamens with yellow tips. These small flowers and divided leaves give the plant its garden interest. Its low stature suits places where gardeners can see these details nearby.

Grow alpine meadow rue in partial shade with humus-rich soil. The soil should stay moist but drain well. The RHS lists both clay and loam as suitable soils. It accepts acid or neutral soil. North-facing and east-facing sites suit its light needs. It can grow in exposed or sheltered spots. The RHS rates it H5 for UK conditions. That rating covers winter lows around 5–14°F (−15 to −10°C). Its need for moisture remains important despite this cold tolerance.

Use it in rock gardens, beds, or flower borders. It also suits containers, patios, courtyards, and informal cottage gardens. Its compact size allows it to fit into small planting spaces. Raise new plants from seed or divide established clumps. Cut back spent flower stems in late autumn. Alternatively, remove them in spring before fresh growth begins. Watch for slugs, which may attack the plant. Dry conditions can also bring powdery mildew. Keep its preference for moist soil in mind when choosing a site.