Subalpine spirea, rose meadowsweet
Photos: © Mike Tyler Jr, © 1999 Thayne Tuason and Derrick Ditchburn
600 to 3050 m (1,4)
Found throughout the
Olympic and Cascade Mountains in
Grows at edges of streams and lakes, in montane meadows, gaps in the forest, wooded and rocky slopes and in open subalpine forests. It prefers to grow in moist soils, in full sun to light shade. (1,4)
Plant strategy type/successional stage
Mid-seral to climax
Found in the Tsuga mertensiana - Xerophyllum tenax association, which includes mountain huckleberry (Vaccinium membranaceum), pipsissewa (Chimaphila umbellata), grouseberry (Vaccinium scoparium), Geyer’s sedge (Carex geyeri), coiled lousewort (Pedicularis contorta) and pink wintergreen (Pyrola asarifolia) (6)
Also associated with
western hemlock (Tsuga heterophylla),
marsh marigold (Caltha biflora),
May be collected as:
Softwood cuttings, hardwood cuttings, seed, rhizomatous offshoots, layered cuttings. (5)
Collection restrictions or guidelines
Collect seeds when follicles are dry and begin to open in fall, cutting capsules into paper bags for collection. Seeds should be light tan when they have reached maturity. Seed should remain in a well-ventilated dry area while awaiting cleaning and sowing. (3)
Recommended 48 to 75 day cold-moist stratification. Roll seeds in moist paper towels and store in open plastic bags in 3°C refrigeration. (3)
Seed longevity is unknown. (3)
Recommended seed storage conditions
Seeds should be kept in cool, well-ventilated storage area.
Softwood cuttings: Collect one-year-old softwood cuttings into plastic bags in early summer and kept refrigerated until processing. Cuttings should be 15-20 cm long and roughly 8 mm caliper. Larger cuttings may be directly planted into 1 gallon containers. Rooting may be aided by application of 5000 ppm liquid IBA (indole butyric acid). (3)
Seeds: Seeds should be sown shallowly or on surface of medium, as they require light for germination. (3)
Soil or medium requirements
Cuttings should be grown in mistbed in 50% perlite and 50% sand with bottom heat (12 cm below medium) kept at 21°C. Outdoor mistbeds should remain covered with shadecloth throughout rooting phase. (3)
Seeds are successfully grown in a mix containing:
-70% 6:1:1 milled sphagnum peat, perlite, and vermiculite
-30% sand with slow release fertilizer (3)
Usually outplanted as a container plant with high establishment success. Fibrous rootballs of container stock must be well loosened or scored before outplanting. (3)
Recommended planting density
Space plants 18-36 inches apart.
Care requirements after installed
Newly planted individuals must be watered regularly during establishment; soil should not dry completely between waterings. (3)
Normal rate of growth or spread
Plants grow very rapidly following establishment. (3)
1. Rose, R., C.E.C. Chachulski
and D.L. Haase.
1998. Propagation of
2. PLANTS Database. United States Department of Agriculture. . Accessed 27 May 2006.
3. Native Plant Network. Native Plants Propagation Protocol Database. http://nativeplants.for.uidaho.edu/network/ Accessed 27 May 2006.
4. Hitchcock, C.L. and A. Cronquist. 1973. Flora of the
5. Dave’s Garden. http://davesgarden.com/pf/go/75346/. Accessed 22 May 2006.
Vegetation of Eastern Washington and
7. Spiraea densiflora. WTU Herbarium Image
Alaine Sommargren, 1 June 2006