Red Spiderling

Boerhavia coccinea

About the Plant

Red spiderling is a prostrate perennial native to the desert Southwest, perhaps native to the Old World as well. It is certainly found worldwide and is considered a weed in most places. The slender, hairy stems can stretch more than a yard from the plant's center. You will most often find this plant in disturbed or waste places, especially at road or curb edge.

Red spiderling begins growing with the monsoon rain and flowers soon after. The tiny but bright red flowers are quite noticeable but overall the plant is not ornamental.

Notes: The other common summer-blooming four o'clocks in our area are Coulter spiderling (Boerhavia coulteri) and trailing windmills (Allionia incarnata).

More Information

Weekly Plant on summer-blooming four o'clocks

Map of distribution in US (blue indicates plant present but not native)

Technical botanical description from SEINet

ID Characteristics

This plant is in the Nyctaginaceae - the four o'clock family.
Red spiderling grows only a few inches high. Long horizontal stems spread in all directions. Leaves are reduced in size and number toward the ends of the stems.
The stem is hairy and just a little sticky (less sticky than the stems of Coulter spiderling or trailing four o'clock). The leaves are opposite and usually of slightly different sizes. The larger leaf is 1.25 - 2 inches long with a petiole 1/4-1/2 inch long. The blade ("leafy" part of the leaf) is 1-1.5 inches long, round, almost as wide as long. The edges are wavy, so the leaf does not lie flat, and the leaves are often edged in red. A side shoot grows from the base of the smaller leaf.
The flowers are tiny and held in a cluster of 5 flowers. The clusters may be close together, making the whole flower group look larger. Usually the flower heads together create clusters no more than 1/4 inch wide. Five sepals (there are no petals) are fused together. In our area, the flowers are red or very deep pink.