Common Name: Steeplebush

General Information

Spiraea douglasii is an erect to ascending, much-ranched, deciduous shrub that can grow from 100 - 300cm tall[]. The plant can spread freely at the roots, usually forming thickets[].
The plant is harvested from the wild for local use as a medicine and source of materials. It is often grown as an ornamental and has been used in breeding programmes to develop ornamental hyrids[].

Known Hazards

None known

Botanical References

,

Range

Western N. America - Alaska, British Colombia, Washington, Oregon, Idaho, California

Habitat

Stream banks, moist woodland margins, wet meadows, fens, swamps, roadsides; at elevations up to 2,500 metres[]. Almost always found in wet soils in redwood and red fir forests[].

Properties

Medicinal Rating
Other Uses Rating
Habit	Deciduous Shrub
Height	2.50 m
Pollinators	Birds, Butterflies, Insects
Cultivation Status	Ornamental, Wild

Cultivation Details

Spiraea douglasii is a very cold hardy plant, tolerating temperatures down to about -25°c[].
Prefers a position in full sun, but also succeeds in light shade[]. Tolerates most soils[], but prefers a good loamy soil with abundant moisture[, ]. Dislikes dry soils[]. Tolerant of seasonal inundation of the soil, the plant is also found in the wild on permanently wet soils[]. Prefers a moist lime-free soil[, ], plants quickly become chlorotic on chalk soils[]. Succeeds in soils with a pH ranging from 4.5 - 7.5[].
Species in this genus generally hybridize freely with other members of this genus, and so seed cannot be relied upon to come true unless the plant has been grown in isolation from other species that are flowering at the same time[].
A rampant suckering shrub, it quickly produces dense thickets and can be used for large-scale naturalistic plantings[]. It is apt to get thin and poor unless divided up fairly regularly and replanted in fairly good soil[, ].
The shoots that flowered the previous summer should be pruned back in late winter or early spring in order to promote better flowering[].

Edible Uses

None known

Medicinal

An infusion of the seeds has been used in the treatment of diarrhoea[].

Agroforestry Uses:

The plant is useful for stabilization of stream-banks and shorelines, as well as the restoration of wetlands including
marshes, bogs, and open swamps[].

Other Uses

The branches have been used to make brooms[].

Propagation

Seed - we have no information for this species but suggest sowing the seed as soon as it is ripe in a cold frame if possible. It is likely to require stratification before it germinates, so stored seed should be sown in a cold frame as early in the year as you receive it. Prick out the seedlings into individual pots when they are large enough to handle, and grow them on in a cold frame for their first winter. Plant them out in late spring or early summer of the following year.
Cuttings of half-ripe wood, mid summer in a light sandy soil a frame.
Cuttings of mature wood of the current seasons growth, 15cm long, autumn in an outdoor frame[]. .
Division of suckers in early spring[]. They can be planted out straight into their permanent positions.