Mustard Greens

Mustard greens (Brassica juncea) are fast-growing leafy brassicas with bold, peppery flavour ranging from mild wasabi-like heat to sharp horseradish intensity depending on the variety. Leaves vary from smooth and lance-shaped to deeply frilled and richly coloured in greens, purples, and crimsons. Plants reach 30–70 cm and thrive in cool conditions, tolerating several degrees of frost — making them ideal for both early and late growing. They bolt in long hot days, so staggered sowings maintain a continuous supply.

Growing

Direct sow seeds 1 cm deep into prepared soil in successive batches, beginning as soon as soil can be worked and continuing through early autumn. Space seeds thinly; thin seedlings to 5–10 cm for baby leaves or 20–35 cm for full plants, keeping row spacing at 35–50 cm. Seeds germinate within 3–5 days once soil is workable. For extra-early or very late harvests, sow in a cold frame or unheated greenhouse. Sowings made in mid-summer consistently produce the finest autumn harvests. No indoor starting is required.

Care

Keep soil consistently moist; mustard greens are shallow-rooted and wilt quickly under drought stress. Apply a balanced liquid feed every two to three weeks on poorer soils. No staking is needed. Remove any yellowing outer leaves promptly to encourage fresh growth. Watch for flea beetle damage on seedlings — fine-mesh insect netting provides effective protection. In hot spells, provide light shade to slow bolting.

Harvest

Begin harvesting outer leaves once plants are a few centimetres tall; regular picking encourages continuous regrowth. For full heads, wait until plants have formed a loose head of 20–35 cm spread. Plants are ready when leaves are firm, crisp, and brightly coloured. Varieties tolerate several degrees of frost and can be harvested well into late autumn. Do not delay harvest once plants begin to send up flower stalks — young flowers are edible but leaves become more pungent.

In the kitchen

Use young leaves raw in salads and wraps where their spicy, wasabi-like bite adds punch. Larger, more mature leaves are excellent lightly stir-fried, steamed, or sautéed — add them at the last moment to retain heat and colour. The peppery flavour mellows significantly with even brief cooking. Pair with sesame oil, soy, garlic, or chilli. Flowers are tender and sweet in stir-fries.

Storing

Harvest leaves dry and store unwashed in a loosely sealed bag in the refrigerator for up to five days. For longer preservation, blanch briefly, cool rapidly in ice water, drain thoroughly, and freeze in portions for up to six months. Alternatively, use larger leaves to make lacto-fermented pickles in the style of Asian kimchi, which keep refrigerated for several weeks.