The Well-Tended Perennial Garden The Essential Guide to Planting and Pruning Techniques, Third Edition

Silphium laciniatum

compass plant

compoSitae

5-in.-wide golden daisies on tall stems;

sandpapery, deeply lobed basal foliage

6–9 ft. (2–4 ft.) high; 2–3 ft. wide

Full sun

Blooms July–August

Zones 3–8

pruning This rugged native prairie

plant has a respectable presence in the

winter garden, and its seedheads serve

as bird food; don’t cut plants down

until late winter. Occasional deadleaf-

ing may be in order during the

growing season.

other maintenance Compass

plant is a striking addition to the

informal wildlife-friendly border.

Plant it in full sun in any type of soil

provided it has decent drainage. Allow

a couple of years for it to become

established and don’t try to move or

divide it once it’s settled in. Silphium

laciniatum develops a deep taproot,

which enables it to survive periods of

drought and live for upward of 100

years on the moderate amount of

rainfall typical of tallgrass prairielands

in the Midwest. Flower stalks may flop

in bad storms. Stakes may be used to

support flower stems if lodging is a

problem, but be sure to use heavy-duty

stakes—the stalks are hefty. Left on

their own, the leaning stems do bring

the flowers down to eye level, which

isn’t all that bad.

related plantS Silphium terebin-

thinaceum, prairie dock, is a similar

taprooted species with bold, unlobed

basal leaves and yellow daisy flowers

on stems that rise as high as 10 ft.

Plant it in all-day sun, or it will lean

toward the light.

Silphium laciniatum