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When to Plant Coreopsis in Jefferson County, WI

Coreopsis (Tickseed) is a cheerful, long-blooming native perennial that produces a continuous flush of bright yellow, gold, or bi-colored daisy-like flowers from early summer well into fall. One of the most reliable cut-and-come-again bloomers in the perennial garden, it thrives in hot, dry, sunny conditions and poor soil where many competitors struggle. An invaluable nectar source for native bees and butterflies, and a butterfly host plant for several species.

Jefferson County, Wisconsin is in USDA Zone 5b. The average last spring frost is April 27 and the first fall frost is October 12, giving you a growing season of approximately 168 days.

At an elevation of 613 feet, Jefferson County receives approximately 36.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Coreopsis during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Jefferson County, WI (Zone 5b) Moderate season
168 days
Last Spring Frost April 27
168 growing days
First Fall Frost October 12

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Coreopsis Planting Timeline — Jefferson County, WI

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Bloom July 20 Jul 20 – Nov 2

Plant 0.1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April
May Transplant Outdoors Direct Sow
June
July Bloom
August Bloom
September Bloom
October Bloom
November Bloom
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

168 days in Jefferson County

Growing Tips for Jefferson County

Start seeds indoors 8–10 weeks before last frost or direct sow after last frost. Seeds germinate easily without stratification. Thrives in poor to average, well-drained soil — rich soil promotes foliage over flowers. Drought tolerant once established; overwatering is the most common mistake. Deadhead spent blooms to maintain continuous flowering through the season. Shear plants by one-third in midsummer for a fresh flush of late-season blooms. Year 2+ plants bloom most heavily. Divide every 2–3 years in early spring to rejuvenate crowded clumps.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Coreopsis in Jefferson County, WI?

Jefferson County is in Zone 5b with an average last frost of April 27. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, WI?

Jefferson County, Wisconsin is in USDA Hardiness Zone 5b. The average last spring frost is April 27 and first fall frost is October 12.

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Your Jefferson County Garden Planner — Free

A 22-page printable planner built for Jefferson County (Zone 5b). 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 Jefferson County, WI. Local conditions may vary. Last updated: June 2026.

Sources & credits

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