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When to Plant Spinach in Jefferson County, PA

Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.

Jefferson County, Pennsylvania is in USDA Zone 5a. The average last spring frost is May 18 and the first fall frost is October 7, giving you a growing season of approximately 142 days.

At an elevation of 1,026 feet, Jefferson County receives approximately 42.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Spinach to ensure they mature before fall.

Jefferson County, PA (Zone 5a) Short season
142 days
Last Spring Frost May 18
142 growing days
First Fall Frost October 7

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (47 days to spare)
Start indoors: Apr 4 Transplant: May 9 🍅 Harvest: Jun 13 – Aug 15
Recommended (50%) ✓ Fits season (44 days to spare)
Start indoors: Apr 13 Transplant: May 18 🍅 Harvest: Jun 22 – Aug 24
Safe Start (90%) ✓ Fits season (50 days to spare)
Start indoors: Apr 27 Transplant: Jun 1 🍅 Harvest: Jul 6 – Sep 7

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.3″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Spinach needs ~521 GDD — county provides 1,739 GDD Excellent fit

Spinach Planting Timeline โ€” Jefferson County, PA

Spinach Planting Calendar

Activity When Date Range
Start Indoors April 13 Apr 13 โ€“ Apr 27
Transplant Outdoors May 18 May 18 โ€“ Jun 1
Direct Sow May 4 May 4 โ€“ May 25
Fall Sowing July 29 Jul 29 โ€“ Aug 12
Harvest June 22 Jun 22 โ€“ Aug 24

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May Transplant Outdoors Direct Sow
June Transplant Outdoors Harvest
July Fall Sowing Harvest
August Fall Sowing Harvest
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

35โ€“50 days

Soil pH

6.5 โ€“ 7.5

USDA Zone

Zone 5a

Growing Season

142 days

Growing Tips for Jefferson County

Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.

Companion Planting

Good Companions

Level Up Your Garden

๐ŸŒพ Save Your Own Spinach Seeds
Life Cycle Annual
Pollination Wind Pollinated
How to Collect Let plants bolt. Harvest seed stalks when seeds turn tan.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Wind pollinated โ€” isolate 1/2 mile for purity. Easy to let bolt in heat.

Frequently Asked Questions

When should I plant Spinach in Jefferson County, PA?

Jefferson County is in Zone 5a with an average last frost of May 18. Plan your Spinach planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, PA?

Jefferson County, Pennsylvania is in USDA Hardiness Zone 5a. The average last spring frost is May 18 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jefferson County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Jefferson County, PA. Local conditions may vary. Last updated: April 2026.