| Plant | Zone 6a | Zone 6b |
|---|---|---|
| Zinnia | Plant outside: May 6 to Jun 10 Start seeds indoors: around Apr 8 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Apr 1 |
| French marigold | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 25 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 18 |
| Petunia | Plant outside: May 6 to Jun 10 Start seeds indoors: around Feb 25 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Feb 18 |
| Cosmos | Plant outside: May 6 to Jun 10 | Plant outside: Apr 29 to Jun 3 |
| Sunflower | Plant outside: May 6 to Jun 10 | Plant outside: Apr 29 to Jun 3 |
| Impatiens | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 11 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 4 |
| Wax begonia | Plant outside: May 6 to Jun 10 Start seeds indoors: around Feb 11 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Feb 4 |
| Zonal geranium | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 11 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 4 |
| Snapdragon | Plant outside: Apr 1 to Apr 29 Start seeds indoors: around Feb 4 Fall planting: Aug 28 to Sep 25 | Plant outside: Mar 25 to Apr 22 Start seeds indoors: around Jan 28 Fall planting: Sep 3 to Oct 1 |
| Pansy | Plant outside: Apr 1 to Apr 29 Start seeds indoors: around Jan 21 Fall planting: Aug 28 to Sep 25 | Plant outside: Mar 25 to Apr 22 Start seeds indoors: around Jan 14 Fall planting: Sep 3 to Oct 1 |
| Sweet alyssum | Plant outside: Apr 1 to Apr 29 Fall planting: Aug 28 to Sep 25 | Plant outside: Mar 25 to Apr 22 Fall planting: Sep 3 to Oct 1 |
| Celosia | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 25 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 18 |
| Scarlet sage | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 11 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 4 |
| Lantana | Plant outside: May 6 to Jun 10 Start seeds indoors: around Feb 25 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Feb 18 |
| Madagascar periwinkle | Plant outside: May 6 to Jun 10 Start seeds indoors: around Feb 25 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Feb 18 |
| Nasturtium | Plant outside: May 6 to Jun 10 | Plant outside: Apr 29 to Jun 3 |
| Sweet pea | Plant outside: Apr 1 to Apr 29 Fall planting: Aug 28 to Sep 25 | Plant outside: Mar 25 to Apr 22 Fall planting: Sep 3 to Oct 1 |
| Larkspur | Plant outside: Apr 1 to Apr 29 Fall planting: Aug 28 to Sep 25 | Plant outside: Mar 25 to Apr 22 Fall planting: Sep 3 to Oct 1 |
| Pot marigold | Plant outside: Apr 1 to Apr 29 Fall planting: Aug 28 to Sep 25 | Plant outside: Mar 25 to Apr 22 Fall planting: Sep 3 to Oct 1 |
| Coleus | Plant outside: May 6 to Jun 10 Start seeds indoors: around Feb 25 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Feb 18 |
| Garden verbena | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 11 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 4 |
| Spider flower | Plant outside: May 6 to Jun 10 | Plant outside: Apr 29 to Jun 3 |
| Floss flower | Plant outside: May 6 to Jun 10 Start seeds indoors: around Mar 11 | Plant outside: Apr 29 to Jun 3 Start seeds indoors: around Mar 4 |
| Moss rose | Plant outside: May 6 to Jun 10 | Plant outside: Apr 29 to Jun 3 |
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 6a.
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.