Radishes. Seed to harvest: 20 to 25 days. ... Baby beets. Seed to harvest: 40 days. ... Turnips. Seed to harvest: 30 to 40 days. ... Kohlrabi. Seed to harvest: 40 days. ... Spinach. Seed to harvest: 30 to 40 days. ... Lettuce. Seed to harvest: 21 to 30 days. ... Arugula. Seed to harvest: 30 days. ... Baby bok choy. Seed to harvest: 30 to 40 days. More items...