1 - The native New Mexico datura (sacred thorn-apple) is not moonflower.
Q. The seeds I enclosed with this letter are from a plant that grows in our pasture about 10 miles west of Anton Chico. They come from a large bushy plant with dark green leaves in the summer. The large, white, trumpet-shaped flowers open at night and are very fragrant. I have enclosed a picture of a moonflower that is similar to the flowers from the plant in the pasture.
What plant is this in the pasture? Is it a moonflower and can I plant these seeds?
Buena Vista, NM
A. The seed pods (burs) that you sent are from the native Datura wrightii, also known as sacred thorn-apple. It is closely related to Jimson weed and is weedy itself. It comes up readily from seeds and from pieces of root left in the ground when you try to dig it up after becoming frustrated with its weedy characteristics. All parts of this plant are toxic if ingested and for that reason alone its use in the landscape is discouraged, to avoid the danger to children and pets. This plant is in the tomato/potato family and may host insects and diseases that create garden problems.
It is tempting to grow this plant because its large, night-blooming flowers are fragrant. However, when tempted to grow this plant, consider the negative characteristics (poison plants that are very difficult to eradicate once established).
The moonflower is a different plant related to the morning glories. It is a plant that grows as a vine rather than a shrub. Like the datura, the moonflower produces its large blossoms at night. It has poisonous seeds (if ingested), but the vine is not hardy and unlikely to become a weed in your landscape. It is hardy to USDA hardiness zone 8 where the temperature stays above 10 degrees. It may regrow each year from seeds, but the new seedlings can be more easily managed than the regrowth of daturas from both seeds and roots. Of the two plants, this would be the more desirable plant for landscape use, even though it will die in the winter. It will be more challenging to grow in New Mexico, but in your location it should grow well if planted in good soil in a location that receives adequate moisture and afternoon shade.
Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: email@example.com, office: 505-865-7340, ext. 113.
For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.
Please copy your County Extension Agent and indicate your county of residence when you submit your question!