Brassica oleracea (Acephala Group) 'Redbor'
Common Name: kale 
Type: Annual
Family: Brassicaceae
Zone: 2 to 11
Height: 1.00 to 1.50 feet
Spread: 1.00 to 1.50 feet
Bloom Time: Flowers not showy
Bloom Description: Rarely flowers
Sun: Full sun
Water: Medium
Maintenance: Low
Suggested Use: Annual, Vegetable
Flower: Insignificant
Leaf: Colorful, Good Fall


Easily grown in organically rich, consistently moist, well-drained loams in full sun. Kale is a cool weather vegetable that is best grown in the cool temperatures of fall. Leaves typically acquire their best flavor after the first fall frost. It may also be grown in early spring. If grown in summer, however, plants will need some afternoon shade, perhaps to simply survive. Plants perform poorly when daytime temperatures begin to consistently exceed 80 degrees F. For spring plantings, sow seed indoors about 6-8 weeks prior to last spring frost date. In the alternative, transplants may be purchased from local nurseries. In either case, the seedlings/transplants should be planted in the garden about 1-2 weeks prior to last spring frost date. For fall plantings, sow seed indoors in early July and plant the seedlings in the garden in mid-August. Plants tolerate light frosts. Depending on temperatures, plants may survive to Thanksgiving or into December in some years. In mild winter climates, plants often survive winter and continue to produce leaves until they bolt in spring. Apply mulch around plants to protect the shallow roots, reduce weeds and retain soil moisture. Rotate crops to avoid soil borne diseases. Plants may also be grown in containers.

Noteworthy Characteristics

Brassica oleracea (Acephala Group), commonly called kale, is a cool weather vegetable that is grown for harvest of its edible leaves. Although very similar to cabbage, kale is distinguished by having loose, upright, wavy-edged leaves that do not form a head (acephala from Greek means headless). Cabbage forms heads. Leaves are typically light green to blue green, but ornamental kales (grown primarily for ornamental foliage) come in leaf colors ranging from purple to red to pink to white. Acephala Group also includes genetically similar spring greens and collard greens. Kale is a biennial that is grown in St. Louis as an annual. Plants will grow to 18" tall. Leaves may be harvested when they reach the approximate size of a human hand. Kale belongs to the Brassica family which includes other cool season vegetables such as cabbage, Brussels sprouts, broccoli, cauliflower and kohlrabi.

Genus name comes from the classical Latin name for cabbage.

Specific epithet means of the vegetable garden.

'Redbor' features purple-red leaves. It is primarily grown in gardens as an ornamental foliage plant rather than as a vegetable. The curled purple-red leaves with silver tones add intense color, texture and interest to garden areas. It is a biennial that is grown in St. Louis as an annual. Plants will grow to 18" tall. Plants need the cool weather of spring or fall to develop their best foliage color. As night temperatures drop during the fall, the leaf color of ‘Redbor’ darkens and intensifies.


Watch for cabbageworms, cabbage loopers, flea beetles, caterpillars, thrips, slugs and aphids. Root maggots may be a problem in some areas. Potential disease problems include leaf spots, blackleg, black rot and yellows.

Garden Uses

Border fronts, ornamental garden areas, edging, window boxes, containers. Mix with chrysanthemums, grasses and asters. Leaves may be harvested as a vegetable, but taste is somewhat inferior to that of kales developed for vegetable gardens. Red leaves may be used as an attractive garnish.