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When to plant Coreopsis in Martin County, MN

Martin County sits in USDA Zone 5a. Plant Coreopsis between May 4 (after last frost on April 27) and May 25.

When to Plant Coreopsis in Martin County, MN

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.

Martin County, Minnesota is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 8, giving you a growing season of approximately 164 days.

At an elevation of 984 feet, Martin County receives approximately 34.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°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
Martin County, MN (Zone 5a) Moderate season
164 days
Last Spring Frost April 27
164 growing days
First Fall Frost October 8

Martin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.9

Drainage

Well Drained

Monthly Watering Guide for Coreopsis

Coreopsis needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Coreopsis Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.3" 1" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 4.1" 0.2" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Coreopsis Planting Timeline — Martin County, MN

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 – Oct 26

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

Low — drought tolerant

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

164 days in Martin County

Growing Tips for Martin 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 Martin County, MN?

Martin County is in Zone 5a 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 Martin County, MN?

Martin County, Minnesota is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 8.

When should I plant Coreopsis in Martin County, MN?

In Martin County, MN, plant Coreopsis after the last frost (around April 27) and before the first frost (around October 8). Best results when soil holds above 50°F.

What growing zone is Martin County, MN for Coreopsis?

Martin County sits in USDA Zone 5a. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Martin County's climate?

Yes — Coreopsis grows well in Martin County's temperate climate. Martin County averages a 164-day frost-free season, with last frost around April 27 and first frost around October 8.

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Your Martin County Garden Planner — Free

A 22-page printable planner built for Martin County (Zone 5a). 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 Martin County, MN. Local conditions may vary. Last updated: July 2026.

Sources & credits

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