What seedlings can you start in January? This post is focused primary on those who live in Zones 5,6,7. What Seedlings Can you Start in January Letâs face it, there really isnât much that most of us can be starting in January. But with a little creativity (and maybe a cold frame) There are a few garden plants that you can get started in January. Even if you live in zones 5 to 7.