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When to Plant Coreopsis in Custer County, OK

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.

Custer County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 8 and the first fall frost is October 31, giving you a growing season of approximately 206 days.

At an elevation of 767 feet, Custer County receives approximately 31.6 inches of rainfall annually with predominantly loam soil. Summer highs average 89°F, providing good warmth for Coreopsis during the growing season.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Custer County, OK (Zone 7b) Long season
206 days
Last Spring Frost April 8
206 growing days
First Fall Frost October 31
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Custer County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

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 0.8" 0" ❄️ Dormant
Feb 1.1" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 5.4" 0" ✅ Rainfall sufficient
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 1.9" 2.4" 🚿 Regular watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

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

Coreopsis Planting Timeline — Custer County, OK

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow April 8 Apr 8 – Apr 29
Bloom June 17 Jun 17 – Nov 4

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November Bloom
December
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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 7b

📆 Growing Season

206 days in Custer County

Growing Tips for Custer 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 Custer County, OK?

Custer County is in Zone 7b with an average last frost of April 8. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Custer County, OK?

Custer County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 8 and first fall frost is October 31.

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Your Custer County Garden Planner — Free

A 22-page printable planner built for Custer County (Zone 7b). 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 Custer County, OK. Local conditions may vary. Last updated: June 2026.

Sources & credits

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