Issue: February 15, 2003

Broom dalea plants

I have seen some grayish-green shrubs along the highway south of Albuquerque. Right now they just look like sticks, but last summer they had lots of small purple flowers. What is this? Are these plants available in the nurseries? Tom B. Albuquerque

From your description, I think you have seen the plant called broom dalea (Psorothamnis scoporia). This is one of our native plants that is very well adapted to our hot, dry environment. Broom dalea grows in the deep sandy soils of the mesa regions around Albuquerque, northward to the Jemez and southward to El Paso. At maturity, it is often 3 feet high and 3 to 4 feet across. It is a useful plant in dry areas where it will receive little or no supplemental irrigation. In arroyos, its twiggy growth is good for slowing water flow and reducing erosion. Broom dalea grows best in deep, well-drained soils that are common to the mesas. It does not grow well in the valley soils if they contain clay and hold too much water.

Bees will actively forage broom dalea and produce an excellent honey. Flower production is greatest in years with good monsoon rains.

It is listed among the plants sold by some native plant and xeriscape-oriented nurseries. Call the nurseries to see if it is available.

Rocky Mtn. zinnia

What is Rocky Mountain zinnia? Is it a good plant for New Mexico landscapes?

Rocky Mountain zinnia (also called Prairie or Plains zinnia) is a member of the daisy, or sunflower family that is very well adapted to our xeric gardening environment. Its scientific name is Zinnia grandiflora, so it is indeed a zinnia but not like the zinnia commonly sold as a garden plant. The Rocky Mountain zinnia is a perennial and doesn't need to be planted each year. It is not as subject to powdery mildew fungus problems and is much lower growing. Its flowers are yellow, small, and produced in large numbers in late spring, then it continues to produce scattered flowers through the summer until frost.

As a perennial, it has a tendency to spread but is not weedy. It needs very little water and will die if over-watered. This zinnia will grow best in well-drained soils. In winter, it turns brown and can be left in place to protect the soil from wind erosion. It may be trimmed back to near ground level before growth begins in the spring.

This is an excellent plant for our water conserving landscapes.

Also, please join us on Southwest Yard & Garden, a weekly program made for gardeners in the Southwest. It airs on KRWG in Las Cruces Saturdays at 11:30 a.m., repeating Thursdays at 1:00 p.m.; on KENW in Portales on Saturdays at 10:00 a.m.; and on KNME in Albuquerque on Saturdays at 9:30 a.m.

Send your gardening questions to Yard and Garden, ATTN: Dr. Curtis Smith NMSU Cooperative Extension Service 9301 Indian School Road, NE, Suite 112 Albuquerque, NM 87112

Curtis W. Smith, Ph.D., is an Extension Horticulture Specialist with New Mexico State University's Cooperative Extension Service. New Mexico State University is an equal opportunity/affirmative action employer and educator.

Please join us on Southwest Yard & Garden, a weekly garden program made for gardeners in the Southwest on: KNME-TV Albuquerque at 9:30 p.m. Saturdays, KENW-TV Portales at 10 a.m. Saturdays, and KRWG-TV Las Cruces at 11:30 a.m. Saturdays (repeated at 1 p.m. Thursdays.)