Boston, MA · zone 6b · ~209 frost-free days
When to plant in Boston: frost dates and zone 6b.
In Boston, the typical last spring frost lands around Apr 9 and the first fall frost around Nov 4, giving you about 209 frost-free days. Cool-season crops go out before the last frost; warm-season crops wait until after it.
The 2026 windows
Sow dates for Boston, keyed to your frost.
| Crop | Start indoors | Spring sow / set out | Fall sow |
|---|---|---|---|
| Tomato, slicing | Mar 5 to May 5 | Apr 16 to Jun 16 | — |
| Lettuce, leaf | — | Mar 2 to Apr 16 | Aug 21 to Oct 20 |
| Carrot | — | Mar 2 to Apr 4 | Aug 9 to Sep 4 |
| Bush Bean | — | Apr 9 to May 30 | Jul 21 to Aug 23 |
| Cucumber, slicing | — | Apr 16 to Jul 16 | — |
| Pepper, bell | Mar 14 to May 5 | Apr 25 to Jun 16 | — |
| Kale | Jan 19 to Feb 16 | Mar 2 to Mar 30 | Aug 4 to Sep 19 |
| Spinach | — | Feb 16 to Mar 30 | Aug 21 to Oct 9 |
Boston sits in Zone 6b, but two gardens in the same city can be a week or two apart. The planner works from your ZIP code's frost dates, not the zone, so the dates land right for your block, not the metro average.
Build your Boston garden plan.
Tell the free planner what you want to eat and who you're feeding. It returns plant counts, spacing, and frost-safe sow dates for ZIP 02108 in about 60 seconds.
Boston planting questions
What planting zone is Boston, MA?+
Boston is in USDA hardiness zone 6b. Growing zone, gardening zone, and planting zone all mean the same thing: the USDA number, 6b here. It tells you what survives winter, not when to plant. Frost dates set your planting time, and the free planner uses your exact ZIP code's frost dates, which can differ by weeks across one metro.
When is the last frost date in Boston?+
The typical last spring frost in Boston, MA is around Apr 9. That is an average from local history, not a guarantee, so tender crops like tomatoes and peppers are safer with a week of buffer after it.
When is the first frost date in Boston?+
The typical first fall frost in Boston, MA arrives around Nov 4, closing a growing season of roughly 209 frost-free days. Count backward from it to find the last date a fall crop can still finish.
What can I plant now in Boston?+
It depends on the date. Cool-season crops like lettuce, kale, and spinach go out weeks before the last frost; warm-season crops like tomatoes and peppers wait until after Apr 9. The table above shows each crop's window; the free planner turns your ZIP into an exact, dated calendar.