Baltimore, MD Frost Dates & Growing Season

The two dates every Baltimore garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Mar 24
~50% chance of frost after
First fall frost
Nov 21
~50% chance of frost before
Growing season
242 days
frost-free stretch
USDA zone
7b
2023 hardiness map
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Mar 8 Mar 24 Apr 4
First fall frost Dec 8 Nov 21 Nov 7
Hard freeze (28°F), median last Mar 11 · first Dec 5

Computed from NOAA 1991–2020 climate normals at the Md Sci Ctr Baltimore station (1 km from central Baltimore). "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Baltimore

Computed from Baltimore's own frost dates. Click any crop for the full zone-7 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Jan 27 – Feb 10 Mar 31 – Apr 7
🫑 Peppers Jan 13 – Jan 27 Apr 7 – Apr 14
🥬 Lettuce Feb 10 – Feb 24 Feb 24 – Mar 10 Feb 24 – Mar 24
🫛 Peas Feb 10 – Feb 24
🥕 Carrots Mar 3 – Mar 24
🥦 Broccoli Feb 3 – Feb 17 Mar 3 – Mar 17
🥬 Kale Feb 10 – Feb 24 Feb 24 – Mar 10 Feb 24 – Mar 10
🥒 Cucumbers Feb 24 – Mar 3 Mar 31 – Apr 7 Mar 31 – Apr 7
🥒 Zucchini Feb 24 – Mar 3 Mar 31 – Apr 7 Mar 31 – Apr 7
🫘 Green Beans (Bush) Mar 31 – Apr 7
🌽 Sweet Corn Mar 31 – Apr 7
🌿 Basil Feb 10 – Feb 24 Mar 31 – Apr 7 Apr 7 – Apr 14
🧄 Garlic Fall: Oct 10 – Nov 7

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Baltimore's dates automatically after a lookup.

Reading the season in Baltimore

With roughly 242 frost-free days, Baltimore gardens fit long-season crops — melons, winter squash, sweet potatoes — with room left for spring and fall rounds of greens and roots. The first frost around Nov 21 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in Baltimore, MD?

The average last spring frost in Baltimore is around Mar 24, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Baltimore, MD?

The average first fall frost in Baltimore arrives around Nov 21. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Baltimore?

About 242 frost-free days on average, from Mar 24 to Nov 21. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is Baltimore in?

USDA zone 7b on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.