Swede

Swede (Brassica napus) is a cool-season brassica producing either large, sweet storage roots or nutritious leafy greens depending on the variety group. Root types form dense, round bulbs with yellow or white flesh that deepens in flavour after frost exposure. Leaf types such as Siberian kale produce broad, flat, frost-tolerant leaves with white or reddish midribs. All forms thrive in open, fertile ground in full sun to partial shade.

Growing

Direct-sow seeds 1 cm deep into well-prepared, firm soil once the soil has warmed to at least 5 °C. For swede root varieties, sow thinly and thin seedlings to 15–20 cm apart in rows 40–50 cm apart. For kale types, thin to 50 cm each way. Kale varieties can also be started indoors 4–6 weeks before transplanting: sow at around 20 °C for rapid germination (4–7 days), then move seedlings to a bright, cool location above 14 °C to prevent legginess. Harden off transplants thoroughly before planting out once frost risk has passed. For swede roots intended for storage, sow later in the season to time bulking before the first hard frosts.

Care

Keep soil consistently moist, especially during root development — irregular watering causes split or woody roots. Apply a balanced fertiliser at planting and a nitrogen-rich feed once plants are established. Firm the soil around transplants to prevent wind rock. Cover young plants with fine mesh to exclude cabbage root fly and flea beetle. Remove any yellowing leaves promptly to improve airflow and reduce disease pressure. Swede roots benefit from a potassium-rich soil; address any boron deficiency with foliar or soil amendments to prevent hollow root.

Harvest

Harvest kale leaves once they reach a usable size by cutting outer leaves individually — the plant continues to produce. Flavour improves significantly after the plants experience frost. For root swedes, lift roots when they have reached a uniform round shape and a diameter of 10–15 cm. Roots left in the ground after the first frosts develop a sweeter, nuttier flavour. Lift before the ground freezes hard, twisting off the tops to within a few centimetres of the root crown.

In the kitchen

Root swedes are excellent roasted, mashed, added to stews and soups, or eaten raw grated in slaws. Their sweet, earthy flavour pairs well with butter, black pepper, and root vegetables. Kale leaves can be eaten raw in salads when young and tender, or sautéed, blanched, or added to soups and stir-fries when mature. Both root and leaf forms are highly nutritious, rich in vitamin C and fibre.

Storing

Swede roots store exceptionally well: keep them in a cool (1–4 °C), dark, humid cellar or clamp for up to 4–6 months. Alternatively, store in boxes of slightly damp sand. Once cut, wrap tightly and refrigerate for up to 2 weeks. Kale leaves keep in the refrigerator for up to 1 week; blanch and freeze for storage up to 12 months. Roots can also be diced and frozen after blanching.