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When to Plant Thyme in Carbon County, PA

Thyme is a low-growing perennial herb with tiny, aromatic leaves and a warm, earthy flavor. It is one of the most versatile culinary and medicinal herbs.

Carbon County, Pennsylvania is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 19, giving you a growing season of approximately 176 days.

At an elevation of 1,110 feet, Carbon County receives approximately 44.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Thyme to ensure they mature before fall.

Carbon County, PA (Zone 5b) Moderate season
176 days
Last Spring Frost April 26
176 growing days
First Fall Frost October 19

Carbon County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (37 days to spare)
Transplant: Apr 26 🍅 Harvest: Jul 5 – Sep 6
Recommended (50%) ✓ Fits season (36 days to spare)
Transplant: May 3 🍅 Harvest: Jul 12 – Sep 13
Safe Start (90%) ✓ Fits season (32 days to spare)
Transplant: May 21 🍅 Harvest: Jul 30 – Oct 1

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.

Soil Compatibility in Carbon County

How your county's soil matches Thyme's growing requirements.

Soil pH

Your soil pH (4.8โ€“6.2) is more acidic than Thyme prefers (6.0โ€“8.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Carbon County is excellent for Thyme โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.5%). Annual compost additions will help Thyme.

How to Plant Thyme

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Thyme

2
successive plantings in your 176-day season

Sow every 8 weeks. Last sowing by Jul 21 to harvest before frost.

Plant Water Budget

Plant needs
0.3″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Thyme needs ~1,040 GDD — county provides 2,288 GDD Excellent fit

Thyme Planting Timeline โ€” Carbon County, PA

Thyme Planting Calendar

Activity When Date Range
Transplant Outdoors May 3 May 3 โ€“ May 17
Harvest July 12 Jul 12 โ€“ Sep 13

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.3"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

70โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“8 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

176 days in Carbon County

Growing Tips for Thyme in Carbon County

Direct sow Thyme outdoors after April 26 in Carbon County when soil has warmed and frost danger has passed.

General growing tips

Start from seed, cuttings, or divisions. Plant in well-drained, lean soil. Prune lightly after flowering. Replace plants every 3-4 years when they become woody.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Thyme in Carbon County, PA?

Carbon County is in Zone 5b with an average last frost of April 26. Plan your Thyme planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Carbon County, PA?

Carbon County, Pennsylvania is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Carbon County gardeners in Zone 5b 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 Carbon County, PA. Local conditions may vary. Last updated: April 2026.