Portland, ME · zone 5b · ~172 frost-free days

When to plant a garden in Portland.

In Portland, the typical last spring frost lands around Apr 26 and the first fall frost around Oct 15, giving you about 172 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 Portland, keyed to your frost.

CropStart indoorsSpring sow / set outFall sow
Tomato, slicingMar 22 to May 22May 3 to Jul 3
Lettuce, leafMar 19 to May 3Aug 1 to Sep 30
CarrotMar 19 to Apr 21Jul 20 to Aug 15
Bush BeanApr 26 to Jun 16Jul 1 to Aug 3
Cucumber, slicingMay 3 to Aug 2Jun 14 to Jul 15
Pepper, bellMar 31 to May 22May 12 to Jul 3
KaleFeb 5 to Mar 5Mar 19 to Apr 16Jul 15 to Aug 30
SpinachMar 5 to Apr 16Aug 1 to Sep 19

Portland sits in Zone 5b, 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 Portland 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 04101 in about 60 seconds.