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When to plant Coreopsis in Sherburne County, MN

Coreopsis planted in Sherburne County between May 8 and May 29 matures in 60–80 days — well before the October 6 first frost.

When to Plant Coreopsis in Sherburne County, MN

Sherburne County, Minnesota Zone 4b June

Your June planting checklist for Sherburne County, Minnesota

June is a pivotal month for Sherburne County, Minnesota gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 1
Avg. first frost October 6
Soil temp (4") 65°F
Watering Low
Pest pressure High
Daylight 15.5 hrs
Looking ahead to July
  • Starting indoors: coreopsis
  • First harvests: coreopsis

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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.

Sherburne County, Minnesota is in USDA Zone 4b. The average last spring frost is May 1 and the first fall frost is October 6, giving you a growing season of approximately 158 days.

At an elevation of 568 feet, Sherburne County receives approximately 38.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Coreopsis to ensure they mature before fall.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Sherburne County, MN (Zone 4b) Moderate season
158 days
Last Spring Frost May 1
158 growing days
First Fall Frost October 6

Sherburne County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.1

Drainage

Well Drained

Coreopsis Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 14 Transplant: May 9 🌸 Bloom: Jul 25 – Oct 17
Recommended (50%) ✗ May not fit
Start indoors: Feb 20 Transplant: May 15 🌸 Bloom: Jul 31 – Oct 23
Safe Start (90%) ✗ May not fit
Start indoors: Mar 9 Transplant: Jun 1 🌸 Bloom: Aug 17 – Nov 9

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 Sherburne County

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

Soil pH

Your soil pH (6.0–7.1) is within Coreopsis's preferred range (5.5–7.5).

Soil Texture

The silt loam soil in Sherburne County is excellent for Coreopsis — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.8%). Annual compost additions will help Coreopsis.

How to Plant Coreopsis

0.1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Coreopsis

3
successive plantings in your 158-day season

Sow every 6.9 weeks. Last sowing by Jul 18 to harvest before frost.

Coreopsis Water Budget

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Coreopsis

Coreopsis needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Coreopsis Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 3.8" 0" ❄️ Dormant
May 2.2" 4.2" 0" ✅ Rainfall sufficient
Jun 2.2" 4.9" 0" ✅ Rainfall sufficient
Jul 2.2" 4.1" 0" ✅ Rainfall sufficient
Aug 2.2" 4.1" 0" ✅ Rainfall sufficient
Sep 2.2" 3.4" 0" ✅ Rainfall sufficient
Oct 2.2" 2.8" 0" ✅ Rainfall sufficient
Nov 2.7" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Sherburne County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Coreopsis Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Coreopsis needs ~805 GDD — county provides 1,817 GDD Excellent fit

Coreopsis Planting Timeline — Sherburne County, MN

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors February 20 Feb 20 – Mar 6
Transplant Outdoors May 15 May 15 – May 29
Direct Sow May 8 May 8 – May 29
Bloom July 31 Jul 31 – Oct 23

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
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

158 days in Sherburne County

Growing Tips for Coreopsis in Sherburne County

Direct sow Coreopsis outdoors after May 01 in Sherburne County when soil has warmed and frost danger has passed.

Common pests for Coreopsis in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Sherburne County, MN?

Sherburne County is in Zone 4b with an average last frost of May 1. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sherburne County, MN?

Sherburne County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 1 and first fall frost is October 6.

When should I plant Coreopsis in Sherburne County, MN?

In Sherburne County, MN, plant Coreopsis after the last frost (around May 1) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Sherburne County, MN for Coreopsis?

Sherburne County sits in USDA Zone 4b. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Sherburne County's climate?

Yes — Coreopsis grows well in Sherburne County's temperate climate. Sherburne County averages a 158-day frost-free season, with last frost around May 1 and first frost around October 6.

🌱

Your Sherburne County Garden Planner — Free

A 22-page printable planner built for Sherburne County (Zone 4b). 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 Sherburne County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.