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When to Plant Crocus in Lehigh County, PA

Crocuses (Crocus spp.) are the heralds of spring — small, gem-like blooms that push up through frozen ground or even snow, often weeks before any other flower. Their compact corms naturalize readily in lawns, rock gardens, and borders, creating drifts of purple, white, and yellow that expand year after year. Bees prize early crocus as one of their first nectar and pollen sources of the season. The saffron crocus (C. sativus) blooms in fall and yields the world's most expensive spice.

Lehigh County, Pennsylvania is in USDA Zone 7a. The average last spring frost is April 20 and the first fall frost is October 24, giving you a growing season of approximately 187 days.

At an elevation of 376 feet, Lehigh County receives approximately 44.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Crocus during the growing season.

Bulb Blooms in Spring Pollinator-friendly Fragrant
Lehigh County, PA (Zone 7a) Moderate season
187 days
Last Spring Frost April 20
187 growing days
First Fall Frost October 24
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Lehigh County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Crocus Planting Timeline — Lehigh County, PA

Crocus Planting Calendar

Activity When Date Range
Bloom August 15 Aug 15 – Sep 5
Fall Sowing September 19 Sep 19 – Oct 3

Plant 4" deep · 3" apart · Rows 4" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June
July
August Bloom
September Fall Sowing Bloom
October Fall Sowing
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

10–20 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

187 days in Lehigh County

Growing Tips for Lehigh County

Plant corms 3–4 inches deep and 2–3 inches apart in fall, when soil temperature drops below 60°F. Mass plantings (at least 25 corms per cluster) create the most visual impact. Plant in well-drained soil — corms rot in standing water. Crocus naturalize well under deciduous trees; the tree leafs out after crocus dormancy begins, so light competition is minimal. Squirrels and chipmunks dig corms — plant deeper (4 inches) or use wire mesh baskets in high-predation areas. Allow foliage to die back naturally before mowing lawns. In zones 8a–8b, plant in December with pre-chilled corms for best results.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Crocus in Lehigh County, PA?

Lehigh County is in Zone 7a with an average last frost of April 20. Plan your Crocus planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lehigh County, PA?

Lehigh County, Pennsylvania is in USDA Hardiness Zone 7a. The average last spring frost is April 20 and first fall frost is October 24.

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Your Lehigh County Garden Planner — Free

A 22-page printable planner built for Lehigh County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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

Sources & credits

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