Penstemon (rydbergii)

Lee Riley Horticulturist USDA FS - Dorena Genetic Resource Center 34963 Shoreview Road Cottage Grove, Oregon 97424 541-915-7324 541-767-5709 (fax) lee.riley@usda.gov

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Family Scientific Name:	Scrophulariales
Family Common Name:	Figwort
Scientific Name:	Penstemon rydbergii
Common Name:	Rydberg’s penstemon
Species Code:	PERY
Ecotype:	Crater Lake National Park
General Distribution:	Lower 48 states
Propagation Goal:	Plants
Propagation Method:	Seed
ProductType:	Container (plug)
Stock Type:	262 ml (16 in3) container
Time To Grow:	18 weeks
Target Specifications:	Stock Type: Container seedling Root System: Firm plug in container.
Pre-Planting Treatments:	Seeds are placed in a solution of 250 mg/L GA3, soaked for 24 hours, rinsed, and soaked for an additional 4 hours in water. Seeds are sown into trays filled with stabilized medium plugs (Q-plugs). Trays are sealed inside plastic boxes and placed into cold stratification (1 to 3 °C) for 90 days. Trays are checked weekly and kept moist throughout the stratification period. If mold is evident, trays should be treated with 1% hydrogen peroxide.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Greenhouse growing facility. Q-plugs are lightly covered with nursery grit. Seedlings are transplanted to target containers when germination complete and secondary leaves have appeared (approximately 4 weeks following removal from stratification). Growing medium in the transplant containers consists of 40:20:20:20 peat:composted fir bark:perlite:pumice with Nutricote controlled release fertilizer (18N:6P2O5:8K2O with minors; 180-d release rate at 21C) at the rate of 1.5 gram Nutricote per 262 ml container.
Establishment Phase:	Germination is fairly uniform and is usually complete in 2 to 3 weeks. Following germination (while still in Q-plugs), plants are fertilized with soluble 12-2-14-6Ca-3Mg at 75 to 100 ppm for 2 weeks.
Length of Establishment Phase:	3 to 4 weeks
Active Growth Phase:	During the growing season, fertilization depends on weather and physiological needs. Soluble 20-9-20 NPK, 20-18-18 NPK, or 17-5-24 NPK at 100 to 150 ppm is applied weekly throughout the growing season.
Length of Active Growth Phase:	14 weeks
Hardening Phase:	No dry-down is done to induce dormancy. Seedlings are moved to an outdoor growing area in mid-September.
Length of Hardening Phase:	3 to 4 weeks depending on chilling hours
Harvesting, Storage and Shipping:	Harvest Date: Mid to late October Storage Conditions: Seedlings are usually outplanted in fall. No storage except in outdoor growing area. Plants are well irrigated prior to shipping if shipped in containers.
Other Comments:	Perennial herb. Found in Arizona, California, Colorado, Idaho, Montana, New Mexico, Nevada, Oregon, Utah, Washington, and Wyoming. Recognized by pollination ecologists as attracting large numbers of native bees. Does best in well-drained soils. Prefer full sun, but will tolerate partial shade. Can be found on moderately moist to dry slopes, meadows, and streambanks. Grows from 1300-3300 meters in elevation.
References:	Dorena Genetic Resource Center Propagation Records, unpublished. Lady Bird Johnson Wildflower Center. Penstemon rydbergii A. Nelson. URL: https://www.wildflower.org/plants/result.php?id_plant=PERY (Accessed 28 February 2024). USDA Natural Resources Conservation Service. Penstemon rydbergii A. Nelson. Rydberg's penstemon. URL: https://plants.usda.gov/home/plantProfile?symbol=PERY (Accessed 28 February 2024).

Citation:

Riley, Lee E.; Klein, Kassandra. 2024. Propagation protocol for production of Container (plug) Penstemon rydbergii Plants 262 ml (16 in3) container; USDA FS - Dorena Genetic Resource Center Cottage Grove, Oregon. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2025/02/25). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.