Propagation of Colorado Native Plants

2004 Annual Report for FW02-007

Project Type: Farmer/Rancher
Funds awarded in 2002: $7,500.00
Projected End Date: 12/31/2005
Region: Western
State: Colorado
Principal Investigator:

Propagation of Colorado Native Plants


The idea was to propagate Colorado native plants using methods that could apply to the greenhouse and nursery industry. The project studied specific native plants and developed general propagation methods that applied to the plants.

The study determined the germination conditions for more than three dozen herbaceous species. The result is that germination rates very widely for the same species depending on seed source and other factors not determined but probably related to seed viability and dormancy. The study also determined seed germination protocols. Many species can be cutting-propagated, which is necessary if a desirable selection is made. The project developed procedures for propagation by cutting.

Two woody riparian species are also being studied, and the results of those will be available in the next report.

To date, results show the need to be flexible in propagating native plants. Methods used one year or on one batch of seed may not work the next time. Farmers and growers wishing to grow native plants must be aware of these vagaries and take steps to deal with them in their operations.

The objective of this study is to increase the availability of native herbaceous species by generating practical knowledge about how to propagate the plants, grow them in containers and winter them over.

Most native plants are grown from seed. Extensive information on germinating ornamental and native species from seed is available from books, journal articles, the Internet, government publications and even seed catalogs and suppliers. Sometimes the information is general (sow in the fall) to specific (sow seed in flats and keep moist at 68-72 F for 2 weeks, then store at 35-38 F for 4 weeks, then germinate at 65-68 F). Sometimes the information is conflicting, one reference saying that a cold stratification period is necessary, another that sowing at 70F yields satisfactory results.

To refine the knowledge about how to propagate native plant species by sowing seed, project coordinator Ann Grant conducted several screening and germination studies, beginning with the screening of several wildflower species in the fall of 2001 to determine germination conditions, followed by additional studies in the fall and winter of 2002.

Based on strong interest in growing Callirhoe involucrate, Purple Poppy Mallow or Winecups, a drought-tolerant, extremely hardy groundcover, Grant also conducted germination studies in the fall of 2001 and 2002 to ascertain propagation practices.

Further, Grant assessed the propagation of native plants from cuttings. Among the plants tested were Agastache, Artemisa, Callirhoe involucrate, Oenothera, Penstemon, Salvia, Scutellaria and Verbena.

Finally, she conducted studies on two woody riparian species, beaked hazelnut (Corylus cornuta) and three-lobed sumac (Rhus trilobata).

(For specific results of these studies to date, contact Western Region SARE communications specialist Ron Daines at 425.755.5749 or [email protected]. Or contact Grant at the address, email or phone number listed in this report.)

Native plants are increasingly in demand. With a small investment, growers can produce a high value crop in a small greenhouse. Native plants in Colorado mean low water, low fertilizer and low maintenance to the home gardener. The inclusion of native plants in the landscape can decrease water use and obviate the need for fertilizers. More qualitative benefits will be cited in the final report.

Other growers have shown interest in the results, some of which have already been shared informally at conferences and meetings.

Protocols for growing natives will be made at the conclusion of the study, although it is doubtful that any new hypotheses will be developed. The project coordinator cited several logistical difficulties in conducting the study, including the request by Western SARE to include in the project woody species, about which the coordinator had little knowledge. Indeed, the time required to write the grant proposal, revise it, especially the budget, and write the report has taken hours and days longer than anticipated. Further, grant dollars were not disbursed until a year after the proposal was submitted. “Better timing of the granting of funds with the growing season on the part of WSARE and better judgment and planning on the part of this grower would have generated better results.”

The plan is to publish a brochure on propagation of native plant, which can be distributed through Master Gardeners and Colorado Native Plant Society. Summary articles will be written and published in various trade publications, including the Looseleaf, the newsletter of the Colorado Greenhouse Growers and Nursery Association, Colorado Gardener, a local gardening magazine, and on the coordinator’s Web site, Talks are planned at the annual meeting of the Colorado Native Plant Society and ProGreen, a conference of the Colorado green industry held each January.