Siler montanum aka Siler Montanum

Siler montanum is a perennial in the Apiaceae family. Garden sources also list it as Laserpitium siler. It comes from mountains in southwestern and central Europe. It grows in woods and among rocks on mountain slopes. Kew places it in the temperate climate zone. It is not native to Britain or Ireland. Its mountain and woodland habitats help explain its garden uses.

This plant forms a rounded clump and loses its leaves seasonally. Its deeply cut leaves have a blue-green cast. The foliage gives the clump a bold shape in borders. Garden plants reach about 1.6–3.3 feet [0.5–1 metre] tall. Their spread ranges from 0.3–1.6 feet [0.1–0.5 metres]. The RHS gives these as its mature garden size ranges. The leaves and flower heads provide its main visual features.

Large umbels carry flowers in shades of pink and white. The RHS places flowering in early summer. Chicago Botanic Garden lists bloom periods from May through August. These records suggest that the flowering season varies between gardens. The flowers offer value to pollinating insects. After bloom, gardeners can keep the seed heads through winter. This gives the plant a role beyond its flowering season. Chicago lists it for bedding and border planting.

The RHS recommends full sun and soil that drains well. It suggests a dry site in gravel or rock gardens. Chicago also lists partial shade, but describes the soil as moist. Plants For A Future includes sunny woodland edges and dappled shade. These sources differ on moisture, so site guidance is not uniform. Chicago lists USDA hardiness zones 4–7. The RHS describes the plant as hardy. It reports few usual pest or disease problems. The plant needs no routine shaping, though spent flowers can be removed. Gardeners may cut it back in autumn or keep seed heads.

Fresh seed can be sown in autumn. The RHS also describes a staged treatment before sowing. This uses damp vermiculite, three warm weeks, then about eight cooler weeks. Plants For A Future records roots and seeds as condiments. It gives the plant a low food-use rating. The same source records a traditional use for toothache. That record does not establish medical safety or effectiveness. It reports no known hazards, but gives no pet-specific safety evidence.