Perennial of the Month-- May 2005 

(ass-tran' chee-ah) (pronunciation at link, turn up volume if too low)

Common name: Masterwort

Family: Apiaceae (Umbelliferae), Carrot

Height x width: 1-3' x 18"

Growth rate; habit: moderate, upright

Foliage: The lower leaves are deeply lobed, on short petioles and toothed; stem leaves are sessile and attached around the stem, seldom toothed; may be tinged purple

Flowers: dark red, said to be darkest of genus; typically flowers of genus 2-3" and pink or greenish-white; a compound umbel of sterile (long flower stalks or pedicels) and fertile (short stalks) flowers; surrounded by a collar of papery bracts (colored leaves), creating a star-like effect

Hardiness: USDA zones 5-7 (although has lived for several years in zone 4a, Vermont)

Soil: prefers consistent soil moisture, organic

Light: part shade south, grows well in sun in cool north if sufficient moisture

Pests and problems: none significant

Landscape habit, uses: border, edge of woodland, cut flower (lasts 10-14 days)

Other interest: from Hadspen House nursery and gardens, Somerset, England and Nori Pope; cross originally made in 1988, so correctly not listed under species major as are most cultivars; this and other species and cultivars more popular in Britain than U.S.; astrantia means aster (a star) in Greek, which refers to the shape of the flowers.

Other culture: prefers cool night temperatures for best growth; may self sow or make up large clumps under good culture

Propagation: division of black roots in fall or early spring, division of runners, seedlings (seed should be cold stratified)

Sources: specialty perennial nurseries local and online, Sunny Border Nurseries (2005, wholesale only)