Blue Mustard

Genus Chorispora
Mustard Family (Brassicaceae/Cruciferae)

Blue mustard plants

Blue Mustard
(Chorispora tenella)

Most species in the mustard family have yellow or white blossoms, but this one has small purple flowers.

The blossoms are very tiny (about 1/4 inch across), with four petals and four sepals -- the pattern of a typical mustard. The plant is usually less than a foot tall.

The plant is a native of the high deserts of southern Russia, in southwestern Asia. It is very drought tolerant, so it has spread rapidly here in this similar climate.

Close-up of blue mustard flowers

I have seen thick patches of this, forming a purple blanket along the roadsides in the spring. It blooms at about the same time, and is the same color as Storksbill (Erodium). The two plants and their blossoms really do not look at all alike, but because of the similar color and the small blossom size, they need to be examined closely in order to see the difference.

It has an unpleasant odor. If eaten by dairy cattle, it will give the milk a disagreeable taste.