| Plant | Zone 4a | Zone 4b |
|---|---|---|
| Basil | Plant outside: May 19 to Jun 23 Start seeds indoors: around Apr 7 | Plant outside: May 15 to Jun 19 Start seeds indoors: around Apr 3 |
| Parsley Annual in zone 4 | Plant outside: Apr 14 to May 12 Start seeds indoors: around Feb 3 | Plant outside: Apr 10 to May 8 Start seeds indoors: around Jan 30 |
| Cilantro | Plant outside: Apr 14 to May 12 Fall planting: Aug 10 to Sep 7 | Plant outside: Apr 10 to May 8 Fall planting: Aug 13 to Sep 10 |
| Dill | Plant outside: Apr 14 to May 12 | Plant outside: Apr 10 to May 8 |
| Chives Comes back in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Spearmint Comes back in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Rosemary Annual in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Common thyme Annual in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Greek oregano Annual in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Garden sage Annual in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Lemon balm Comes back in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| French tarragon Comes back in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Lemongrass Annual in zone 4 | Plant outside: May 19 to Jun 23 | Plant outside: May 15 to Jun 19 |
| Bronze fennel Annual in zone 4 | Plant outside: Apr 14 to May 12 | Plant outside: Apr 10 to May 8 |
| German chamomile | Plant outside: Apr 14 to May 12 | Plant outside: Apr 10 to May 8 |
| Stevia Annual in zone 4 | Plant outside: May 19 to Jun 23 | Plant outside: May 15 to Jun 19 |
| Lovage Comes back in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
| Garden sorrel Comes back in zone 4 | Spring: Apr 28 to Jun 23 Fall: Jul 20 to Aug 17 | Spring: Apr 24 to Jun 19 Fall: Jul 23 to Aug 20 |
Zones measure winter cold, not season length, so your own frost dates can be a week or two off the zone median. Look up your frost dates by ZIP code, or read all about zone 4a.
Hardiness ranges, light and size are typical figures from university extension services and botanic garden plant records; a named variety can differ, so check its tag. Planting dates come from each zone's median frost dates (NOAA 1991 to 2020 climate normals) and the timing rules in how we check.