Geranium maderense 'Guernsey White'

Common name: Giant herb-Robert

Description: A dramatic, architectural perennial grown for its huge, finely dissected, glossy green leaves that form an imposing rounded mound. In its second or third year it sends up a tall, branching flower spike smothered in masses of flat white blooms with deep pink centres, usually in late spring to early summer, before the plant sets seed and dies.

Other benefits: striking architectural foliage, excellent specimen for a sheltered border or large container, self-seeds readily

Wildlife attraction: The abundant summer flowers are attractive to bees and other pollinating insects.

Height & spread (approx.) at 10 years: Up to 1.2m x 1m at maturity (this is a short-lived, monocarpic plant that flowers in its second or third year then dies, often self-seeding to renew the display)

Position: Full sun for the best flowering display, though it appreciates light afternoon shade in hot summers; choose a sheltered spot away from strong winds.

Soil pH: Neutral soils suit it well; tolerates a range of well-drained garden soils including sandy and chalky types.

Moisture: Prefers well-drained soil with moderate, regular moisture and does not like to sit wet, especially over winter.

Winter hardiness: Tender; hardy down to around -4°C to -5°C in sheltered, frost-free gardens — needs winter protection or a frost-free spot in most of the UK outside the mildest coastal areas.