Heirloom Kohlrabi Seed
(Brassica oleracea)
Heirloom / Open Pollinated Kohlrabi is a hardy biennial grown as an annual. Kohlrabi seeds can be started indoors 4-6 weeks before the last frost, then set out transplants when there are 6-8 true leaves and nighttime temps remain above 30°F. Direct sow Kohlrabi seeds 3-4 weeks before the last frost in spring, or in late summer for a winter harvest. Plant Kohlrabi in full sun, ¼ – ½” deep, 1″ apart in rows 12-18″ apart. Thin Kohlrabi plants to or set out transplants 3-8″ apart. Germination of Kohlrabi seeds should occur in 5-17 days in soil 55-75°F. For extended harvest of Kohlrabi, stagger plantings throughout a month in spring or fall plantings. For tender sweet Kohlrabi, harvest when stem reaches 2″ in diameter. For general use and storage crop harvest at 3-5″ in diam. Fall Kohlrabi crops will remain hardy to 10°F.