Penstemon (speciosus)

Ann DeBolt and Hilary Parkinson USDA FS - Rocky Mountain Research Station 316 E. Myrtle Boise, Idaho 83702 208-373-4366 208-373-4391 (fax) adebolt@fs.fed.us www.fs.fed.us/rm/boise

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Family Scientific Name:	Scrophulariaceae
Family Common Name:	Figwort family
Scientific Name:	Penstemon speciosus Dougl.
Common Name:	Showy penstemon, Sagebrush penstemon
Ecotype:	Owyhee uplands and canyons, Malheur County, OR, 1180 m
General Distribution:	Central Washington, eastern Oregon, and southwestern Idaho to California and Utah. Typically in Artemisia tridentata communities.
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Time To Grow:	0
Propagule Collection:	The dark blue to purple flowers bloom from May to July. Phenology varies based on elevation, aspect and seasonal weather patterns. The fruit (a capsule) is mature when it turns brown and opens partially. This typically occurs 5 to 8 weeks after flowering. Seed ripening is quite uniform, with a collection window of approximately 2 to 3 weeks. Seeds are a dull brown and number 400,000-500,000/lb. The capsules were collected by cutting the mature inflorescence (a raceme) with clippers and placing them in containers. After collection, the capsules were thoroughly dried and placed in a standard freezer for 48 hours to remove insect pests.
Propagule Processing:	Capsules are removed from stems and crushed on a rubbing board. Material is then passed through sieves with 1.7 and 1.0 mm square openings (Nos. 12 and 18 USA STS). Fine debris is removed using a seed blower.
Pre-Planting Treatments:	Seed was soaked in 250 ppm giberellic acid for approximately 24 hours and then placed in germination boxes on two layers of blotter paper moistened with distilled water. Additional water was added as needed. Seed was prechilled at 4§C in the dark for 60 days. Mold began to form in the germination boxes after 30 days. The blotter paper was replaced and seeds were washed with Thiram, an anti-fungal seed protectant. After the 60 days of prechilling, seeds were incubated in a germinator at a constant 21§C with exposure to 12 hours of cool-white fluorescent light alternating with 12 hours of darkness.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Upon first signs of germination, seeds were sown 0.25-0.5 cm deep in styrofoam conetainers filled with a 50% peat and 50% vermiculite mixture. Soil was watered from an automatic overhead irrigation system that turns on when soil saturation levels fall below 80%, and turns off when it reaches 100% field capacity. Greenhouse temperature was a constant 27§C. Small amounts of fertilizer suitablefor seedlings were added periodically.
Establishment Phase:	Germination of prechilled seeds began after 3 days of incubation and germination was complete after 4 days. Tetrazolium tests (Idaho State Seed Laboratory) determined that viability was 73% and purity 90% (66% PLS). 33% of the seed germinated (50/150). An extended period of cold moist stratification (beyond 60 days) is recommended. Only 26% of the germinants developed into healthy seedlings in the greenhouse.
Other Comments:	Partial funding for this research was provided by the USDI Bureau of Land Management, Great Basin Restoration Initiative. The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department of Agriculture of any product or service. This publication reports research involving pesticides. It does not contain recommendations for their use, nor does it imply the uses discussed here have been registered. All uses of pesticides must be registered by appropriate State and/or Federal agencies before they can be recommended. CAUTION: Pesticides can be injurious to humans, domestic animals, desirable plants, and fish or other wildlife, if they are not handled or applied properly. Use all pesticides selectively and carefully. Follow recommended practices for the disposal of surplus pesticides and pesticide containers.
References:	Hitchcock, C. Leo, and Arthur Cronquist. 1973. Flora of the Pacific Northwest. University of Washington Press, Seattle, WA. 730 p. USDA, NRCS. 2004. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Citation:

Parkinson, Hilary; DeBolt, Ann. 2005. Propagation protocol for production of Container (plug) Penstemon speciosus Dougl. plants USDA FS - Rocky Mountain Research Station Boise, Idaho. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/12/23). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.