Collards are one of the few vegetables on our list that actually become tastier with frost. Both cold-tolerant and heat-tolerant, collards are an understated, easygoing crop. According the Heirloom Organics website, collards can tolerate slightly alkaline soil and drought. Quality of leaves may suffer under these conditions, so it’s best to grow collards in a cool, moist atmosphere with balanced soil and plenty of sunshine. One recommended variety is Champion, which can be harvested in 60 days and has a reputation for cold tolerance.