White mustard (Sinapis alba) is commonly used as a cover crop in European agriculture (see Col d’Orcia in Montalcino for an example in vineyards). Early vigour is important to cover the soil quickly and suppress weeds and protect the soil against erosion. Resistant white mustard varieties significantly reduce nematode populations by excreting sulphur compounds from its roots which inhibit eelworms [nematodes] and slugs.

Mustard seed is used as a spice. Grinding and mixing the seeds with water, vinegar, or other liquids creates the yellow condiment known as prepared mustard. The seeds can also be pressed to make mustard oil, and the edible leaves can be eaten as mustard greens.

The mustard plant is a plant species in the genera Brassica and Sinapsis in the Brassica (Brassicaceae) family.