Seed-Starting Date Calculator
The right time to start your seeds indoors varies significantly by crop and ranges anywhere from 2–16 weeks prior to transplanting. Use this calculator to ascertain when to start seeds indoors and then to transplant outside, based on the frost-free date in your area.
Enter spring frost-free date (include year):
| Crop | Number of weeks to start seeds before setting-out date | When to start inside | Setting-out date | |||
|---|---|---|---|---|---|---|
| From | To | Safe time to set out plants (relative to frost-free date) | From | To | ||
| Artichoke | 8 |
19-Jul |
on frost-free date |
13-Sep |
||
| Basil | 6 |
9-Aug |
1 week after |
20-Sep |
||
| Beets* | 4 to 6 |
19-Jul |
2-Aug |
2 weeks before |
30-Aug |
|
| Broccoli | 4 to 6 |
19-Jul |
2-Aug |
2 weeks before |
30-Aug |
|
| Cabbage | 4 to 6 |
5-Jul |
16-Aug |
4 weeks before |
16-Aug |
13-Sep |
| Cauliflower | 4 to 6 |
19-Jul |
16-Aug |
2 weeks before |
30-Aug |
13-Sep |
| Celery & Celeriac | 10 to 12 |
28-Jun |
12-Jul |
1 week after |
20-Sep |
|
| Collards | 4 to 6 |
5-Jul |
19-Jul |
4 weeks before |
16-Aug |
|
| Corn Salad/Mâche | 4 to 6 |
21-Jun |
26-Jul |
3 to 6 weeks before |
2-Aug |
23-Aug |
| Corn* | 2 to 4 |
16-Aug |
13-Sep |
0 to 2 weeks after |
13-Sep |
27-Sep |
| Cucumber | 3 to 4 |
23-Aug |
6-Sep |
1 to 2 weeks after |
20-Sep |
27-Sep |
| Eggplant | 8 to 10 |
19-Jul |
9-Aug |
2 to 3 weeks after |
27-Sep |
4-Oct |
| Kale | 4 to 6 |
5-Jul |
19-Jul |
4 weeks before |
16-Aug |
|
| Kohlrabi* | 4 to 6 |
5-Jul |
19-Jul |
4 weeks before |
16-Aug |
|
| Leeks | 8 to 10 |
21-Jun |
5-Jul |
2 weeks before |
30-Aug |
|
| Lettuce | 4 to 5 |
12-Jul |
26-Jul |
3 to 4 weeks before |
16-Aug |
23-Aug |
| Melons | 3 to 4 |
30-Aug |
6-Sep |
2 weeks after |
27-Sep |
|
| Mustard* | 4 to 6 |
5-Jul |
19-Jul |
4 weeks before |
16-Aug |
|
| Okra* | 4 to 6 |
16-Aug |
13-Sep |
2 to 4 weeks after |
27-Sep |
11-Oct |
| Onions | 8 to 10 |
7-Jun |
21-Jun |
4 weeks before |
16-Aug |
|
| Parsley | 9 to 10 |
14-Jun |
28-Jun |
2 to 3 weeks before |
23-Aug |
30-Aug |
| Peas* | 3 to 4 |
21-Jun |
12-Jul |
6 to 8 weeks before |
19-Jul |
2-Aug |
| Peppers | 8 |
2-Aug |
2 weeks after |
27-Sep |
||
| Pumpkins | 3 to 4 |
30-Aug |
6-Sep |
2 weeks after |
27-Sep |
|
| Spinach | 4 to 6 |
21-Jun |
26-Jul |
3 to 6 weeks before |
2-Aug |
23-Aug |
| Squash | 3 to 4 |
30-Aug |
6-Sep |
2 weeks after |
27-Sep |
|
| Swiss Chard | 4 to 6 |
19-Jul |
2-Aug |
2 weeks before |
30-Aug |
|
| Tomatoes | 6 to 8 |
26-Jul |
16-Aug |
1 to 2 weeks after |
20-Sep |
27-Sep |
| Watermelon | 3 to 4 |
30-Aug |
6-Sep |
2 weeks after |
27-Sep |
|
|
|
||||||
| Ageratum | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Agrostemma (Corn Cockle)* | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Amaranthus | 4 to 6 |
9-Aug |
23-Aug |
1 week after |
20-Sep |
|
| Ammi (False Queen Anne's Lace)* | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Artemisia (Sweet Annie) | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Asclepias (Butterfly Weed) | 10 to 12 |
21-Jun |
5-Jul |
on frost-free date |
13-Sep |
|
| Aster, China | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Bells of Ireland** | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Calendula* | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Cardoon | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Carthamus (Safflower)* | 4 to 6 |
2-Aug |
16-Aug |
on frost-free date |
13-Sep |
|
| Castor Bean | 6 to 8 |
26-Jul |
9-Aug |
1 week after |
20-Sep |
|
| Celosia | 6 to 8 |
26-Jul |
9-Aug |
1 week after |
20-Sep |
|
| Centaurea (Bachelor's Button)* | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Chinese Lanterns | 8 to 12 |
21-Jun |
19-Jul |
on frost-free date |
13-Sep |
|
| Coleus | 8 |
26-Jul |
1 week after |
20-Sep |
||
| Cosmos* | 5 to 7 |
26-Jul |
9-Aug |
on frost-free date |
13-Sep |
|
| Craspedia (Drumstick Flower) | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Datura (Angel's Trumpet) | 8 to 12 |
5-Jul |
9-Aug |
2 to 3 weeks after |
27-Sep |
4-Oct |
| Delphinium | 10 to 16 |
24-May |
5-Jul |
on frost-free date |
13-Sep |
|
| Dianthus (Sweet William) | 10 to 12 |
7-Jun |
28-Jun |
1 to 2 weeks before |
30-Aug |
6-Sep |
| Digitalis (Foxglove) | 10 to 12 |
21-Jun |
5-Jul |
on frost-free date |
13-Sep |
|
| Eucalyptus | 10 to 12 |
21-Jun |
5-Jul |
on frost-free date |
13-Sep |
|
| Euphorbia (Snow-on-the-Mountain)* | 4 to 6 |
2-Aug |
16-Aug |
on frost-free date |
13-Sep |
|
| Flower Collections & Mixes* | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Forget-Me-Not | 8 to 9 |
12-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Gaillardia (Blanket Flower) | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Gomphrena (Globe Amaranth) | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Helianthus maximillianii | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Hibiscus | 8 to 10 |
12-Jul |
26-Jul |
1 week after |
20-Sep |
|
| Hollyhock | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Hyacinth Bean | 4 to 6 |
9-Aug |
23-Aug |
1 week after |
20-Sep |
|
| Impatiens | 8 to 10 |
12-Jul |
26-Jul |
1 week after |
20-Sep |
|
| Kale, Ornamental | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Larkspur* | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Lisianthus | 12 to 13 |
14-Jun |
21-Jun |
on frost-free date |
13-Sep |
|
| Lupine | 6 to 8 |
5-Jul |
19-Jul |
2 weeks before |
30-Aug |
|
| Marigold | 6 to 8 |
26-Jul |
9-Aug |
1 week after |
20-Sep |
|
| Monarda (Bee Balm) | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Morning Glory | 3 to 4 |
6-Sep |
20-Sep |
3 to 4 weeks after |
4-Oct |
11-Oct |
| Nigella* | 4 to 6 |
2-Aug |
16-Aug |
on frost-free date |
13-Sep |
|
| Phlox** | 4 |
19-Jul |
1 to 2 weeks before |
30-Aug |
6-Sep |
|
| Pepper, Ornamental | 8 |
26-Jul |
1 week after |
20-Sep |
||
| Petunia | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Polygonum (Prince's Feather) | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| California Poppy* | 2 to 3 |
23-Aug |
30-Aug |
on frost-free date |
13-Sep |
|
| Corn Poppy* | 2 to 3 |
23-Aug |
30-Aug |
on frost-free date |
13-Sep |
|
| Iceland Poppy | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Ptilotus | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Rudbeckia (Black-Eyed Susan) | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Salpiglossis (Painted Tongue) | 4 to 6 |
2-Aug |
16-Aug |
on frost-free date |
13-Sep |
|
| Salvia | 6 to 8 |
5-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Sanvitalia | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Scabiosa (Pincushion Flower) | 4 to 6 |
2-Aug |
16-Aug |
on frost-free date |
13-Sep |
|
| Scarlet Runner Bean | 2 to 3 | soil 60 degrees | ||||
| Snapdragon | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Statice | 8 |
19-Jul |
on frost-free date |
13-Sep |
||
| Stock | 8 to 10 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Sunflowers* | 3-4 |
16-Aug |
23-Aug |
on frost-free date |
13-Sep |
|
| Strawflower | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Sweet Pea* | 4 to 6 |
19-Jul |
9-Aug |
1 to 2 weeks before |
30-Aug |
6-Sep |
| Thunbergia (Black-Eyed Susan Vine) | 6 to 8 |
19-Jul |
2-Aug |
on frost-free date |
13-Sep |
|
| Tithonia (Mexican Sunflower)* | 6 |
9-Aug |
1 week after |
20-Sep |
||
| Verbena | 8 to 12 |
21-Jun |
19-Jul |
on frost-free date |
13-Sep |
|
| Viola (Pansy) | 8 to 12 |
7-Jun |
12-Jul |
1 to 2 weeks before |
30-Aug |
6-Sep |
| Yarrow | 8 to 12 |
5-Jul |
19-Jul |
on frost-free date |
13-Sep |
|
| Zinnia | 4 |
23-Aug |
1 week after |
20-Sep |
||
| * Usually direct-sown, but may be started indoors | ||||||
| ** Specifically recommended for direct-seeding outdoors | ||||||
| Note: Dates are the same from year to year, but this table requires a year for computation simplicity. | ||||||