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Showing posts from December, 2018

Saving Zinnia Seeds

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Southwest Yard & Garden by Dr. Marisa Thompson
Question: I have a large monarch butterfly garden, and I gathered zinnia seed heads to plant next spring. Zinnia seeds appear to have two distinct morphologies. The ray flower seed is shield-shaped and the disk flower seed is smaller and flatter. Which of the seeds is viable? I have researched and found some who say only the ray seed, some say only the disk seed, and some say both. Please let me know which zinnia seed is most viable and why. -Tim P., New Mexico
Answer: I know exactly what you mean. I’ve had this question before myself. Zinnias were one of my first garden successes when I moved to Las Cruces in 2009. I too gathered the seed heads and I too wondered which part was the true seed that should be saved. That year I just saved the whole shebang. In the late spring I crunched up the entire dried flowers and sprinkled them around the garden. It worked, so I kept that routine right up to today. Our office building at the NMSU Agri…

Mistletoe: The Kiss of Death (not really! but we should still try to control the spread)

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Southwest Yard & Garden by Dr. Marisa Thompson
Question: What trees are resistant to mistletoe? -John Allen, NMSU Extension Agriculture Agent & Program Director, Socorro County Answer: OK, no one really calls mistletoe “the kiss of death” as I did in this week’s column title. That’s my attempt to grab readers by the eyeballs. Mistletoes don’t tend to kill their tree hosts, but it is possible, and they certainly can do harm, leaving the host plants more vulnerable to other stressors. The genus name for true mistletoe is Phoradendron, which means “tree thief.”
Mistletoe is usually green or at least a puke-green color. Winter is a good time to detect it in deciduous trees because the tree leaves have dropped and the mistletoe is temporarily exposed. Greenness is a clue that mistletoe contains chlorophyll and can photosynthesize on its own, so it’s not necessarily stealing sugars from the host plant. It’s still a parasite because it lacks normal root tissues. Instead of roots, mistlet…

Poinsettias can be “New Mexico True” TOO!

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Southwest Yard & Garden by Dr. Marisa Thompson
Question: I love the poinsettias I bought this year, but one is already starting to droop pretty badly. How do I keep them looking good through the season? -Elizabeth S., Santa Fe
Answer:
Did you know you can purchase locally-grown poinsettias at plant nurseries across the state? I interviewed poinsettia growers in Albuquerque, Santa Fe, Las Cruces, Radium Springs, and Estancia to find out more about poinsettia production in New Mexico, how to get my hands on one (or a few) this season, and how to take care of them at home. The City of Albuquerque Parks and Recreation Department grows its own poinsettias for holiday displays at the Albuquerque International Sunport and various City Hall buildings. I remember being struck by the vibrancy of the gorgeous Sunport poinsettia planters last December. This year, I got to visit the city’s greenhouses twice to check on the growing process. When I first visited in late August, each plant was looking …

Cochineal Scale on Cholla and Prickly Pear

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Southwest Yard & Garden by Dr. Marisa Thompson

Question: What’s the white cottony stuff growing on my cholla cactus? And should I do anything about it?
-Albuquerque resident via Bernalillo County Extension Horticulture Agent, Sara Moran Answer: Although it looks like cotton fibers, that stuff is actually a fine wax produced by adult cochineal scale insects, and little black specks may be their nymphs. It’s common around these parts on cholla (Cylindropuntia spp.) and prickly pear (Opuntia spp.) cacti. The similar-looking white beards on other cacti, like the Peruvian old man (Espostoa lanata) and Peruvian old lady (Espostoa melanostele), are normal, healthy modified tissues, not an insect product. The white waxy coating made by cochineal scale on landscape chollas and prickly pears helps protect these true bugs from predators—and insecticides. I’ve seen prickly pear pads almost completely covered in that white fluff. It’s more common to find mild infestations, like the ones Doña Ana C…