Species (common name, Latin name)

Streambank Hollyhock, Mountain Hollyhock,  Streambank Globemallow; Iliamna rivularis



Wild hollyhock occurs mostly east of the Cascade Range from Alberta and British Columbia to Oregon, east to Montana, and south to Colorado (1)


Climate, elevation

Wild hollyhock commonly grows on forested slopes, in meadows, along streambanks, and in disturbed areas It occurs on mesic sites in deep, moist, but well-drained soil. It has been found to 11,500 feet (3,490 m) elevation in Colorado and 9,570 feet (2900 m) elevation in Utah. (1)


Local occurrence

East side of cascades near foothills and forest openings around mid elevations (2)


Habitat preferences

I. rivularis occurs on moist but well drained soils, it is common in burns and disturbed sites and is considered to be shade intolerant and flowers profusely in the sun. (3)


Plant strategy type/successional stage

rivularis is an early seral species. It becomes abundant following disturbance such as clearcutting, broadcast burning, and wildfire.  (1)


Associated species

Other plants in the Hollyhock family.


May be collected as: (seed, layered, divisions, etc.)



Collection restrictions or guidelines

Seeds are hand collected in late August when capsules turn brown and begin to dehisce. Mature seed color is brown. Seed capsules are collected in paper bags and kept in drying shed prior to cleaning. (3)


Seed germination

Seeds are scarified in a brief, 5 to 10 second hot water bath and immediatlely transferred to cold water and imbibe overnight.Seeds are placed in fine mesh bags in moist peat moss in ventilated containers at 3C for a 30 day cold moist stratification. (3)


Seed life

Seed longevity is at least 10 years under dry cool storage conditions at 3 to 5 C and low relative humidity.(3) Wild hollyhock seeds remain viable for at least a few hundred years (1)


Recommended seed storage conditions

Dry cool storage conditions.


Propagation recommendations

Seed seems to be the easiest way to propagate Hollyhocks.


Soil or medium requirements (inoculum necessary?)

It occurs on mesic sites in deep, moist, but well-drained soil. In greenhouse conditions growing media used is 70% 6:1:1 milled sphagnum peat, perlite, and vermiculite and 30% sand.



Installation form (form, potential for successful outcomes, cost)

Seeds do seem to be considered difficult to germinate.



Care requirements after installed

Seedlings are uppotted into 1 gallon containers in late spring. Irrigate in morning until the pots are leached and irrigation is gradually reduced in September and October. Plants were given one final irrigation prior to winterization (3)



Normal rate of growth or spread; lifespan

Total Time To Harvest: 7 months (3)



Sources cited


1.         Matthews, Robin F. 1993. Iliamna rivularis. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/


2.         University of Washington Herbarium, 6/3/05 (http://www.washington.edu/burkemuseum/collections/herbarium/index.php)


3.         Wick, Dale; Evans, Jeff; Luna, Tara. 2004. Propagation protocol for production of container Iliamna rivularis var. rivularis (Dougl.) Greene plants (116 ml conetainers); Glacier National Park, West Glacier, Montana. In: Native Plant Network. URL: http://www.nativeplantnetwork.org (accessed 6 June 2005). Moscow (ID): University of Idaho, College of Natural Resources, Forest Research Nursery.


Data compiled by (student name and date)

Pat Kendzierski 6/3/05