Seed-Starting Date Calculator

The right time to start your seeds indoors varies significantly by crop and location, ranging 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):

mm/dd/yyyy
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
VEGETABLES
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
FLOWERS
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 can be started indoors
** Specifically recommended for direct-seeding outdoors
Note: Dates are the same from year to year, but this table requires that a year be entered for computation simplicity.