A weed or a native wildflower, Coulter's spiderling depends on the view of the beholder.

Coulter Spiderling is especially noticeable in summer in Southern Arizona. Some call it a weed and others call it a wildflower since it’s a native.

Q:Β I have the weed in the attached picture growing after lots of summer monsoon weather in Tucson. Can you help me identify it?

A:Β The plant is called Coulter’s spiderling (Boerhavia coulteri) and it’s an annual in the four o’clock family (Nyctaginaceae). It can be easily found in washes and flat areas in the Sonoran Desert. I have some in my yard if you need any. It spreads like a groundcover, it produces spikes of tiny pink flowers, and it reproduces by seed. It’s native to the Southwest and found throughout most of the state. It is especially noticeable in summer in Southern Arizona. Some call it a weed and others call it a wildflower since it’s a native. It certainly grows like a weed so you have to decide if you like it enough to keep it or dislike it enough to pull it up before it produces seed.

Peter L. Warren is the urban horticulture agent for the Pima County Cooperative Extension and the University of Arizona. Questions may be emailed to

tucsongardensage@gmail.com


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