S Mtn, PA Frost Dates & Growing Season

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

Last spring frost
Apr 27
~50% chance of frost after
First fall frost
Oct 20
~50% chance of frost before
Growing season
176 days
frost-free stretch
USDA zone
≈ 6b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 13 Apr 27 May 14
First fall frost Nov 2 Oct 20 Oct 6
Hard freeze (28°F), median last Apr 13 · first Nov 1

Computed from NOAA 1991–2020 climate normals at the S MTN station. "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 S Mtn

Computed from S Mtn's own frost dates. Click any crop for the full zone-6 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Mar 2 – Mar 16 May 4 – May 11
🫑 Peppers Feb 16 – Mar 2 May 11 – May 18
🥬 Lettuce Mar 16 – Mar 30 Mar 30 – Apr 13 Mar 30 – Apr 27
🫛 Peas Mar 16 – Mar 30
🥕 Carrots Apr 6 – Apr 27
🥦 Broccoli Mar 9 – Mar 23 Apr 6 – Apr 20
🥬 Kale Mar 16 – Mar 30 Mar 30 – Apr 13 Mar 30 – Apr 13
🥒 Cucumbers Mar 30 – Apr 6 May 4 – May 11 May 4 – May 11
🥒 Zucchini Mar 30 – Apr 6 May 4 – May 11 May 4 – May 11
🫘 Green Beans (Bush) May 4 – May 11
🌽 Sweet Corn May 4 – May 11
🌿 Basil Mar 16 – Mar 30 May 4 – May 11 May 11 – May 18
🧄 Garlic Fall: Sep 8 – Oct 6

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 S Mtn's dates automatically after a lookup.

Reading the season in S Mtn

Roughly 176 frost-free days gives S Mtn gardeners room for nearly every common vegetable. Warm-season crops go out after Apr 27; a fall garden sown in late summer matures comfortably before the Oct 20 frost.

Frequently asked questions

When is the last frost in S Mtn, PA?

The average last spring frost in S Mtn is around Apr 27, 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 S Mtn, PA?

The average first fall frost in S Mtn arrives around Oct 20. 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 S Mtn?

About 176 frost-free days on average, from Apr 27 to Oct 20. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is S Mtn in?

USDA zone 6b 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.