Thalictrum simplex aka Small Meadow Rue

Thalictrum simplex, or simple meadow rue, is a perennial herb. This means it lives for more than two years. It is part of Ranunculaceae, the buttercup family. It comes from the Russian Far East, northern China and Korea. It grows in regions with a temperate climate. It is not native to Britain or Ireland. The plant grows in clumps and sheds its leaves each year. Both its split leaves and its flowers add garden value.

Plants reach about 1.6–3.3 feet (0.5–1 metre) tall. They spread 0.3–1.6 feet (0.1–0.5 metres) wide. They reach full size in two to five years. Each leaf splits into leaflets, each with three lobes. Stems rise above the clump and do not branch. They bear loose panicles, or branched groups of flowers. This shape suits mixed beds. The flowers can stand above the lower plants there.

The small flowers open in June and July. Each has green sepals with a purple flush. These sit around stamens with yellow tips. Though tiny, the blooms make a show in loose groups. Their shape differs from large, single flowers in a border. Suggested uses include cottage gardens and beds with an informal style. Wildflower meadows and open woods also suit this plant. Both the leaves and flowers add to these garden schemes.

For best growth, give it part shade and moist soil rich in humus. It also grows in full sun. Keep the soil moist, but let excess water drain. Chalk, clay, loam and sand all suit the plant. It grows in acid, neutral or alkaline soil. The RHS lists sites both with and without shelter as suitable. It needs a moderate amount of water and care. The RHS rates its hardiness as H6. Missouri Botanical Garden lists USDA zones 7–9. These two systems differ. Read each rating in the context of its region.

Grow new plants from seed or split clumps that have settled in. Cut back spent flower stems in late autumn. You may instead wait until spring, before new growth starts. Slugs may cause harm, so check for signs of feeding. Dry spells can lead to powdery mildew. Smut and rust may occur too. Despite these risks, Missouri Botanical Garden reports no serious insect or disease problems. The supplied evidence for this species does not establish food uses. Nor does it establish whether the plant is toxic.