Zone 6 Seed Starting Calendar. Enter your zip code, and the planting calculator will list the dates for when you should start. Notice that this zone 6 planting calendar shows when you can start plants from seeds, succession plant, and harvest.

Enter your zip code, and the planting calculator will list the dates for when you should start. Start your first seeds inside for broccoli, cabbage, cauliflower, celery, head lettuce, onions, and parsley.