Sinapis arvensis: Wild mustard

Family: Brassicaceae
Common name: Wild mustard, Charlock mustard, Field mustard, Charlock, Corn charlock

Small plants found on roadsides, empty plots, and open areas, Wild mustard plants closely resemble actual mustard in their leaves and flowers. Wild mustard plants can reach a height of .8-1 meter with a stem that’s heavily branched towards the tip and covered with small white hairs.

The plant is fast-growing having 15-20 leaves before it starts flowering and fruiting. The lower leaves are about 8-15 cms long, multi-lobed with toothed margins.

But younger leaves towards the tip are much smaller, 3-6 cms long, elongated oval with smooth margins. Bright yellow flowers are formed on long racemes that branch well, forming many bunches of flowers.

Wild mustard flowers have 4 distinct petals which are spread away from each other. Sepals are cup-shaped but with long green sepals that project almost to the same level as the petals. Stamens and style are also distinctly visible.

These tall, bright flowers attract bees and insects that help pollinate the plant. Fruits are elongated pods 3-5 cms long with a pointy beak and held erect, pointing outwards. These fruits contain many dark brown or black seeds that are 1-1.5 mm in diameter.

The fruit pods split open on maturity releasing the seeds. Interestingly, the seeds can lay dormant for over 50 years in the soil till ideal conditions arise for germination.

The name Sinapis denotes mustard, and arvensis means ‘from the field’. The seeds produce a kind of mustard, but they are toxic to humans and animals causing adverse reactions like stomach pain and vomiting on excess consumption.

Leaves are used in garnishes, potherbs, and salads, sometimes after cooking. Older leaves have a bitter flavor, and hence younger leaves are used for culinary purposes. Flowers and seeds are also eaten raw and cooked, but in moderate quantities.

Seeds can be sprouted or powdered and added to dishes. The seeds yield an edible oil which is used as machinery lubricant.

Wild mustard plants prefer good sunlight, sandy or rocky soil. They can tolerate drought, poor soil conditions, salinity, pollution, and heavy grazing. So they are considered invasive weeds in many parts of the world. In agricultural land, these fast-growing plants can choke small seedlings and deprive them of nutrition.

Propagation is through seeds that have a very good germination rate.