What does a mustard plant look like?

Question: Do mustard plants have yellow or white flowers? What does a mustard plant look like? -Robbie T.

Answer: Mustard plants belong to the Brassica family, with characteristics which range from deeply lobed and frilled foliage to smooth broad leaves. Some mustard plants have yellow flowers, while others bloom in white. Depending on the variety that you grow, mustard’s tiny round1 seeds are either yellow, brown, or black. There are a few overarching characteristics that you can easily use to identify mustard.

One of the best ways to identify mustard plants is by the flower. Whether the bloom is yellow or white, if it consists of four petals and six stamens, you know that it is a mustard flower. The name ‘cruciferous’ refers to this plant family’s four-petaled flowers which form a cross. The six stamens are arranged on the stem in an ‘H’ like shape with four long and two short. There is also a pistil that appears as a fuzzy staff which stands upright in the middle of the flower.

Sinapis alba is yellow or white mustard. The color refers to the seeds which are pitted and either yellow or white. The most commonly cultivated variety, S.alba is a Mediterranean native, which is where most of the condiment mustard is produced. This plant grows to about 3 feet high, with scattered branches and irregular lobed leaves. The yellow flowers have four petals and the seedpods which are tapered and bristly.

Brassica Juncea is a mustard variety that hails from Asia, which is also referred to as brown mustard, chinese mustard, canola, or leaf mustard. This is a very common variety that is grown regularly in Russia and Asia. This variety is used not only as a spice but as a source of cooking oil and leafy greens. The seeds of certain varieties of Brassica juncea are crushed to produce canola oil.

Some mustard green cultivars we are familiar with belong to the Juncea genera such as Mizuna, Crispafolia, and Takana. The flowers of juncea are yellow and similar to other varieties. The leaves, however, are varying. The Mizuna cultivar produces highly frilled and textured greens which are often picked young to add texture to salads. Crispafolia, on the other hand, has smooth leaves that are broad and thick. Brown mustard seed pods typically contain up to 20 seeds compared to yellow seed pods which contain roughly 6 seeds per pod.

Brassica Nigra is a dark brown to black mustard plant that is native to large portions of Africa and regions of India and Asia. This lankier mustard plant variety proudly displays yellow flowers with four petals each. While this less common mustard plant variety is not cultivated as much as other varieties, it is still a highly prized crop, with dark brown to black seeds that are used as a spice commonly found in curries and as accents in gourmet mustards. The seeds of black mustard varieties are crushed and used to produce cooking oil. The smooth but toothed leaves are harvested for greens.