USDA Zone 4a planting calendar
In USDA Zone 4a, the average last spring frost is around 05/14 and the first fall frost around 09/27, giving roughly a 134-day growing season. Plant cool-season crops from late winter; warm-season crops after the last frost.
Last frost ~05/14
First frost ~09/27
~134-day season
26 NOAA stations
The year in Zone 4a
What to plant now (August)
Spinach
Sow for fall harvest
Radishes
Sow for fall harvest
All crops in Zone 4a
| Crop | Start indoors | Transplant / sow | Sow for fall |
|---|---|---|---|
| Tomatoes | April 13 – April 20 | May 18 – June 1 | — |
| Peppers | April 2 | May 21 – June 4 | — |
| Eggplant | April 6 – April 20 | May 25 – June 8 | — |
| Basil | April 13 | May 18 – June 1 | — |
| Broccoli | March 26 – April 2 | April 16 – April 30 | June 18 – July 2 |
| Cabbage | March 5 – March 19 | April 9 – April 23 | May 9 – May 23 |
| Cauliflower | March 19 – April 2 | April 23 – May 7 | June 23 – July 7 |
| Brussels Sprouts | March 12 – March 26 | April 16 – April 30 | — |
| Kale | March 5 – March 19 | April 9 – April 23 | June 28 – July 12 |
| Lettuce | March 16 – March 23 | April 13 – April 27 | June 13 – June 27 |
| Spinach | — | April 6 – April 20 | July 23 – August 6 |
| Onions | February 5 – February 19 | April 9 – April 23 | — |
| Leeks | February 12 – February 26 | April 16 – April 30 | — |
| Swiss Chard | March 19 – March 26 | April 23 – May 7 | — |
| Radishes | — | April 16 – April 30 | August 7 – August 21 |
| Turnips | — | April 16 – April 30 | July 8 – July 22 |
| Beets | — | April 23 – May 7 | July 3 – July 17 |
| Carrots | — | May 7 – May 21 | June 3 – June 17 |
| Peas | — | April 2 – April 16 | June 28 – July 12 |
| Beans | — | May 14 – May 28 | — |
| Sweet Corn | — | May 14 – May 28 | — |
| Cucumbers | April 27 – May 4 | May 18 – June 1 | — |
| Summer Squash & Zucchini | April 30 – May 7 | May 21 – June 4 | — |
| Winter Squash | April 30 – May 7 | May 21 – June 4 | — |
| Pumpkins | April 30 – May 7 | May 21 – June 4 | — |
| Melons | April 30 – May 7 | May 21 – June 4 | — |
| Okra | April 23 – May 7 | May 28 – June 11 | — |
| Potatoes | — | April 27 – May 11 | — |
| Parsley | February 16 – February 23 | April 20 – May 4 | — |
| Collards | March 5 – March 19 | April 9 – April 23 | June 13 – June 27 |
| Watermelon | April 30 – May 7 | May 21 – June 4 | — |
| Sweet Potatoes | — | May 18 – June 1 | — |
| Celery | February 26 – March 12 | May 14 – May 28 | — |
| Kohlrabi | March 5 – March 19 | April 9 – April 23 | — |
| Artichoke | February 19 – March 19 | May 7 – May 21 | — |
| Asparagus | — | April 13 – April 27 | — |
| Cilantro | — | May 14 – May 28 | — |
| Dill | — | April 27 – May 11 | — |
| Oregano | March 12 – March 26 | May 14 – May 28 | — |
| Sage | March 26 – April 9 | May 14 – May 28 | — |
| Thyme | March 12 – March 26 | May 14 – May 28 | — |
Fall bulb planting in Zone 4a
| Crop | Plant cloves (fall) | Harvest |
|---|---|---|
| Garlic | October 1 – October 15 | Following summer |
Last verified 2026-08-28. Frost: NOAA NCEI 1991–2020 Climate Normals. Zone: USDA 2023 Plant Hardiness Zone Map (PRISM-derived). Planting rules: UNH Extension, Johnny's Selected Seeds, UGA Extension.