Seed Starting Calendar by ZIP Code
Enter your ZIP code to see exactly when to start each crop indoors and when to move it outside, counted back from your last spring frost — indoor start, transplant, and direct-sow windows for 40+ vegetables, herbs, and flowers.
| Crop | Method | Start indoors | Transplant out | Direct sow | Weeks before frost |
|---|---|---|---|---|---|
| Tomatoes | Start indoors | Jan 25 – Feb 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 6–8 wks |
| Peppers | Start indoors | Jan 11 – Jan 25 | Mar 29 – Apr 12 | — | 8–10 wks |
| Cucumbers | Start indoors | Feb 22 – Mar 8 | Mar 29 – Apr 12 | Mar 29 – Apr 12 | 2–4 wks |
| Squash (Winter) | Start indoors | Feb 22 – Mar 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 2–4 wks |
| Zucchini | Start indoors | Feb 22 – Mar 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 2–4 wks |
| Beans (Bush) | Direct sow | — | — | Mar 22 – Apr 19 | — |
| Peas | Direct sow | — | — | Feb 8 – Mar 1 | — |
| Lettuce | Start indoors | Feb 8 – Feb 22 | Mar 1 – Mar 15 | Feb 22 – Mar 15 | 4–6 wks |
| Spinach | Start indoors | Feb 8 – Feb 22 | Feb 22 – Mar 8 | Feb 8 – Mar 1 | 4–6 wks |
| Kale | Start indoors | Feb 8 – Feb 22 | Mar 8 – Mar 22 | Feb 22 – Mar 15 | 4–6 wks |
| Broccoli | Start indoors | Jan 25 – Feb 8 | Mar 8 – Mar 22 | — | 6–8 wks |
| Cauliflower | Start indoors | Jan 25 – Feb 8 | Mar 8 – Mar 22 | — | 6–8 wks |
| Cabbage | Start indoors | Jan 25 – Feb 8 | Mar 8 – Mar 22 | — | 6–8 wks |
| Carrots | Direct sow | — | — | Feb 22 – Mar 15 | — |
| Radishes | Direct sow | — | — | Feb 22 – Apr 5 | — |
| Beets | Direct sow | — | — | Feb 22 – Mar 15 | — |
| Onions | Start indoors | Jan 11 – Jan 25 | Mar 8 – Mar 22 | Feb 22 – Mar 8 | 8–10 wks |
| Corn | Direct sow | — | — | Mar 29 – Apr 19 | — |
| Potatoes | Direct sow | — | — | Mar 8 – Mar 29 | — |
| Sweet Potatoes | Start indoors | Jan 25 – Feb 8 | Apr 5 – Apr 19 | — | 6–8 wks |
| Basil | Start indoors | Feb 8 – Feb 22 | Mar 29 – Apr 12 | Mar 29 – Apr 12 | 4–6 wks |
| Cilantro | Direct sow | — | — | Mar 8 – Apr 5 | — |
| Parsley | Start indoors | Jan 25 – Feb 8 | Mar 22 – Apr 5 | Mar 8 – Mar 22 | 6–8 wks |
| Dill | Direct sow | — | — | Mar 15 – Apr 12 | — |
| Rosemary | Start indoors | Jan 11 – Jan 25 | Mar 22 – Apr 5 | — | 8–10 wks |
| Thyme | Start indoors | Jan 25 – Feb 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 6–8 wks |
| Mint | Start indoors | Jan 25 – Feb 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 6–8 wks |
| Melons | Start indoors | Feb 22 – Mar 8 | Mar 29 – Apr 12 | Mar 29 – Apr 12 | 2–4 wks |
| Eggplant | Start indoors | Jan 25 – Feb 8 | Mar 29 – Apr 12 | — | 6–8 wks |
| Celery | Start indoors | Jan 11 – Jan 25 | Mar 15 – Mar 29 | — | 8–10 wks |
| Marigolds | Start indoors | Feb 8 – Feb 22 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 4–6 wks |
| Zinnias | Start indoors | Feb 22 – Mar 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 2–4 wks |
| Sunflowers | Direct sow | — | — | Mar 15 – Apr 12 | — |
| Cosmos | Start indoors | Feb 22 – Mar 8 | Mar 22 – Apr 5 | Mar 22 – Apr 5 | 2–4 wks |
| Nasturtiums | Direct sow | — | — | Mar 15 – Apr 5 | — |
| Petunias | Start indoors | Jan 11 – Jan 25 | Mar 22 – Apr 5 | — | 8–10 wks |
| Snapdragons | Start indoors | Jan 25 – Feb 8 | Mar 8 – Mar 22 | Mar 8 – Mar 22 | 6–8 wks |
| Sweet Peas | Start indoors | Feb 8 – Feb 22 | — | Feb 22 – Mar 15 | 4–6 wks |
| Dahlias | Start indoors | Feb 8 – Feb 22 | Mar 29 – Apr 12 | — | 4–6 wks |
| Lavender | Start indoors | Jan 11 – Jan 25 | Mar 22 – Apr 5 | — | 8–10 wks |
| Morning Glories | Direct sow | — | — | Mar 22 – Apr 12 | — |
| Pansies | Start indoors | Jan 25 – Feb 8 | Feb 22 – Mar 8 | Feb 22 – Mar 8 | 6–8 wks |
| Calendula | Direct sow | — | — | Feb 22 – Mar 15 | — |
| Black-Eyed Susans | Start indoors | Jan 25 – Feb 8 | Mar 22 – Apr 5 | Mar 8 – Mar 22 | 6–8 wks |
| Impatiens | Start indoors | Jan 11 – Jan 25 | Mar 29 – Apr 12 | — | 8–10 wks |
Zone 7 example · last frost ~Mar 22
What to start this week
Summer · June 27The trays to fill right now for Zone 7, counted back from your last frost. When the sowing windows are quiet, we show real seasonal tasks — never filler.
No indoor sowings open this week.
No direct sowings open this week.
- Start fall brassicas and root crops indoors in mid to late summer
- Keep new trays out of the harshest afternoon heat
- Label and date every fall tray as you sow it
Your spring start timeline
Each crop’s indoor start is counted back from your Mar 22 last frost (blue line). Direct-sow crops skip the tray and go straight in the ground after frost.
Start-date details
Start indoors
Direct sow
Showing a Zone 7 example (last frost ~Mar 22). Enter your ZIP for your zone. Updated 2026-06-26.
Common Questions About Starting Seeds
When should I start seeds indoors?
Count back from your last spring frost. Slow growers like peppers, eggplant, and onions want 8 to 10 weeks of indoor time; tomatoes and brassicas about 6 to 8; quick crops like lettuce 4 to 6. Enter your ZIP and the calendar gives you exact start dates for your USDA zone.
Which seeds should I start indoors versus direct sow?
Warm-season fruiting crops (tomatoes, peppers, eggplant) and most brassicas transplant well, so they get an indoor head start. Root crops and legumes — carrots, beans, radishes, peas — resent transplanting and do best sown straight into the ground after frost.
How many weeks before the last frost do I start tomatoes?
About 6 to 8 weeks before your last spring frost, then transplant a week or two after frost once the soil has warmed. The calendar shows both the indoor start window and the transplant window for your zone.
Can I start seeds in summer for a fall garden?
Yes. Brassicas like broccoli, cabbage, and cauliflower are commonly started indoors in mid to late summer for a fall harvest, and quick cool-season crops can be direct sown. Watch the "what to start this week" panel — it surfaces the windows that are genuinely open.
Are these start dates exact?
They are based on USDA zone data, NOAA 30-year frost averages, and university extension timing norms. For a typical year they will be close, but your microclimate and the weather shift real frost dates by a week or two. Treat them as a planning guide and check local conditions.