Garden Detective

Pretty weed becomes nightshade nightmare

Garden Detective: This mystery plant has attractive lavender flowers and silver foliage. It’s silverleaf nightshade, a toxic weed that can be hard to eliminate.
Garden Detective: This mystery plant has attractive lavender flowers and silver foliage. It’s silverleaf nightshade, a toxic weed that can be hard to eliminate.

Experts tackle readers’ garden questions.

Q: What is this plant? It was in my yard when I moved to Rio Linda 14 years ago and, despite my attempts to pull it out, has spread.

Rebecca Parker, Rio Linda

Horticulturist Ellen Zagory: The silver-leaved plant looks like Solanum elaeagnifolium, a weed that I have seen around occasionally.

Its common name is silverleaf nightshade.

Editor’s note: In other parts of the country, this pretty but noxious plant is called white horse nettle, trompillo, prairie berry and tomato weed. It’s a member of the potato family and, like other nightshades, all parts are poisonous.

According to the University of California’s weed database, silverleaf nightshade can be found throughout California below 3,900 feet elevation and is particularly common in desert valleys as well as orchards, pastures, vineyards and along roadsides.

Very drought resistant, this broadleaf perennial can reach 3 feet tall and, once established, is difficult to eradicate. It spreads by creeping underground roots as well as seed. The large leaves are covered with short, dense hairs that give the foliage a silver appearance and this plant its nickname.

From May through September, silverleaf nightshade is covered with showy flowers in shades of purple and lavender or sometimes white and light blue with a bright yellow center. The blooms mature into globe-shaped berries that look like tiny eggplant. These berries start pale green and turn yellow or orange as they ripen. Although toxic if eaten, these berries were used by pioneers to curdle milk to make cheese.

To get rid of this plant, you need to dig down and get those spreading roots. Otherwise, it will just keep resprouting when you try to pull it out. Make sure to wear gloves.

Ellen Zagory is the public horticulture director at the UC Davis Arboretum.

Garden questions?

Questions are answered by master gardeners at the UC Cooperative Extension services in Sacramento and Placer counties. Send questions to Garden Detective, P.O. Box 15779, Sacramento, CA 95852. Send email to h&g@sacbee.com. Please put “Garden Detective” in the subject field and include your postal address. To contact UC Extension directly, call:

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