Packera (cana)

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:	Asteraceae
Family Common Name:	Aster
Scientific Name:	Packera cana
Common Name:	Woolly Groundsel
Species Code:	PACA15
Ecotype:	Central Oregon
General Distribution:	Canada, lower 48 states
Propagation Goal:	Plants
Propagation Method:	Seed
ProductType:	Container (plug)
Stock Type:	262 ml (16 in3) container
Time To Grow:	15 weeks
Target Specifications:	Stock Type: Container seedling Root System: Firm plug in container.
Pre-Planting Treatments:	Due to small seed size, the easiest method is to sow seed 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 120 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 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:	12 weeks
Hardening Phase:	No dry-down is done to induce dormancy. Seedlings are moved to an outdoor growing area in early to 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. Plugs can also be extracted and packed in boxes for shipping and stored in cooler storage for 1 to 2 weeks.
Length of Storage:	Maximum of 1 to 2 weeks in cooler.
Other Comments:	Perennial herb. Prefers rocky sites in mountain shrub, pinyon-juniper, Douglas fir, spruce-fir, and alpine tundra communities. Can be found on talus slopes and high ridges. A host plant for the aphid species Aphis senecionis. Considered to have moderate levels of toxicity, and may be harmful in sufficient quantities. Members of the genus Packera are known to contain toxic alkaloids that can cause liver disease in livestock and humans. Low water usage and prefers full sun.
References:	Dorena Genetic Resource Center Propagation Records, unpublished. Lady Bird Johnson Wildflower Center. Packera cana (Hook.) W.A. Weber & Á. Löve. URL: https://www.wildflower.org/plants/result.php?id_plant=PACA15 (Accessed 28 February 2024). USDA Natural Resources Conservation Service. Packera cana (Hook.) W.A. Weber & Á. Löve. Woolly groundsel. URL: https://plants.usda.gov/home/plantProfile?symbol=PACA15 (Accessed 28 February 2024).

Citation:

Riley, Lee E.; Klein, Kassandra. 2024. Propagation protocol for production of Container (plug) Packera cana Plants 262 ml (16 in3) container; USDA FS - Dorena Genetic Resource Center Cottage Grove, Oregon. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2025/06/07). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.