What Is Mustard Greens? Common Varieties, Characteristics and Planting Times

Mustard greens (Brassica juncea) are annual or biennial herbaceous plants in the genus Brassica of the family Brassicaceae. They are widely cultivated across China and are one of the most common vegetables. Their leaves are broad, and the plants have a distinctive pungent aroma; tasted raw, they are slightly bitter, but after blanching or pickling the flavor becomes much milder.

Mustard greens can be roughly divided into three types according to the part eaten: leaf types, stem types and root types. Common leaf mustards include snow mustard (Brassica juncea var. crispifolia) and large-leaf mustard, which are mostly used to make pickles; the representative stem mustard is zha cai (Brassica juncea var. tumida); root mustard, commonly called mustard tuber or kohlrabi-like turnip, has a swollen fleshy root suited to making pickled vegetables.

As for cultivation, mustard greens prefer a cool, humid climate, and are mostly grown in autumn and winter, though in some regions sowing can be extended into early spring. They are fairly adaptable, their growing period is not long, and in management it is enough to keep up the water supply and control pests such as aphids in good time; they are also relatively easy to grow well in a home vegetable garden.

Many people confuse mustard greens with Chinese kale (gai lan). In fact, the two are not the same. Chinese kale is eaten for its flower stalks and tender leaves, with a crisp texture, whereas mustard greens have a more pronounced pungent flavor and are used more for pickling and processing.

In cooking, mustard greens can be stir-fried plain, used in soups, and are also often processed into flavorful foods such as pickled sour greens and salted vegetables. Because pests easily occur during the growing period, the issue of pesticide residues in mustard greens is often mentioned; it is advisable to soak them thoroughly in clean water and rinse them repeatedly before cooking, and to choose products with intact leaves, normal color and no off odor for greater peace of mind.