Guide to Growing Kale
This vitamin-packed vegetable fell out of favor for a while but is now gaining popularity. It is a hardy and easy-to-grow plant, as architectural as it is flavorful, and brings interest and sustenance to the winter garden.
How to Grow
Kale is a hardy crop and will survive outside in the worst winter weather. It tolerates most soil types but prefers well-drained soil that has been improved with well-rotted organic matter, such as garden compost. It also benefits from firm, compacted soil, which helps support its tall stems. Sow seeds in mid-spring in pots or modules under cover, and plant out in the late spring and early summer. Plant 18 inches (45 cm) apart, being careful not to damage the roots. Firm the plants in, and water thoroughly. Continue to water only sparingly, except in dry conditions, to encourage tougher leaves to overwinter.
Keep plants well weeded, and remove yellowing leaves as they appear. If lots of the leaves start to turn yellow in the early fall, apply a high-nitrogen granular or liquid fertilizer to restore color. If you are growing taller varieties, especially in exposed gardens, stake the plants before they are damaged by strong winds.
Harvest kale from fall to spring, picking the tender leaves from the center of the crown to encourage regrowth. Remove any flowers that appear, but leave the older leaves in place to help protect the center. Harvest until the plants flower; the leaves then turn bitter.
Kale can also be grown as a cut-and-come-again salad. Harvest when 2–3 inches (5–8vcm) high, or later at 6 inches (15 cm). Colorful kale varieties make an attractive winter feature in the garden. They are ideal for smaller plots, allowing you to incorporate vegetables into mixed planting designs.
Types of Kale Available
Curly kale varieties (C) are sweeter-tasting and more tender than traditional smooth-leaf kale. They also look attractive in the garden during winter. In the other hand, smooth-leaf kale (S) is only grown for the tender leaves at the center of the plant. What's more, some varieties of kale can make handsome border plants. Consider these varieties: ‘Dwarf Green Curled’ (C), ‘Redbor’ (C) ‘Reflex’ F1 (C), ‘Scarlet’ (C) and ‘Winterbor’ F1(C) or ‘Black Tuscan’ (S).
Watch Out for These Pests and Diseases
All brassicas suffer from similar pests and diseases. Powdery mildew causes white fungal growth on the leaves and may cause holes to develop. Plants are weakened, reducing yield. Prevalent in dry conditions; ensure that plants are well watered. Whitefly attack the new tender leaves, which are the ones usually picked. Spray heavy infestations with insecticide, and wash before eating.