Blog

When to plant Coreopsis in Miller County, AR

Miller County gardeners should plant Coreopsis between March 7 and March 28 in spring. With Miller County's Zone 8b climate (last frost March 21), Coreopsis needs 60–80 days to mature — plant by August 24 for a full harvest.

When to Plant Coreopsis in Miller County, AR

Miller County, Arkansas Zone 8b June

June in Miller County, Arkansas — your action list

Your garden in Miller County, Arkansas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost March 21
Avg. first frost November 12
Soil temp (4") 84°F
Watering Low
Pest pressure High
Daylight 14.2 hrs
  1. Pick coreopsis

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Get ahead of July
  • First harvests: coreopsis

Instant PDF download. No spam, unsubscribe any time.

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.

Miller County, Arkansas is in USDA Zone 8b. The average last spring frost is March 21 and the first fall frost is November 12, giving you a growing season of approximately 236 days.

At an elevation of 266 feet, Miller County receives approximately 50.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Coreopsis during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Coreopsis root diseases.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Miller County, AR (Zone 8b) Long season
236 days
Last Spring Frost March 21
236 growing days
First Fall Frost November 12

Miller County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7.1

Drainage

Well Drained

Coreopsis Planting Risk Windows

Early Start (70% safe) ✓ Fits season (23 days to spare)
Start indoors: Jan 15 Transplant: Mar 12 🌸 Bloom: May 14 – Oct 8
Recommended (50%) ✓ Fits season (26 days to spare)
Start indoors: Jan 24 Transplant: Mar 21 🌸 Bloom: May 23 – Oct 17
Safe Start (90%) ✓ Fits season (19 days to spare)
Start indoors: Feb 17 Transplant: Apr 14 🌸 Bloom: Jun 16 – Nov 10

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 Miller County

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

Soil pH

Your soil pH (5.3–7.1) overlaps with Coreopsis's range (5.5–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Coreopsis.

How to Plant Coreopsis

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

Succession Planting Coreopsis

4
successive plantings in your 236-day season

Sow every 6.9 weeks. Last sowing by Aug 24 to harvest before frost.

Coreopsis Water Budget

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

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 3.7" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 2.2" 5" 0" ✅ Rainfall sufficient
Apr 2.2" 3.9" 0" ✅ Rainfall sufficient
May 2.2" 4" 0" ✅ Rainfall sufficient
Jun 2.2" 4.6" 0" ✅ Rainfall sufficient
Jul 2.2" 5.7" 0" ✅ Rainfall sufficient
Aug 2.2" 5.1" 0" ✅ Rainfall sufficient
Sep 2.2" 4.1" 0" ✅ Rainfall sufficient
Oct 2.2" 3.4" 0" ✅ Rainfall sufficient
Nov 2.2" 4.1" 0" ✅ Rainfall sufficient
Dec 3.5" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Miller 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 ~1,382 GDD — county provides 4,661 GDD Excellent fit

Coreopsis Planting Timeline — Miller County, AR

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors January 24 Jan 24 – Feb 7
Transplant Outdoors March 21 Mar 21 – Apr 4
Direct Sow March 7 Mar 7 – Mar 28
Bloom May 23 May 23 – Oct 17

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Transplant Outdoors Direct Sow
April Transplant Outdoors
May Bloom
June Bloom
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: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

236 days in Miller County

Growing Tips for Coreopsis in Miller County

Direct sow Coreopsis outdoors after March 21 in Miller 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 Miller County, AR?

Miller County is in Zone 8b with an average last frost of March 21. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Miller County, AR?

Miller County, Arkansas is in USDA Hardiness Zone 8b. The average last spring frost is March 21 and first fall frost is November 12.

When should I plant Coreopsis in Miller County, AR?

In Miller County, AR, plant Coreopsis after the last frost (around March 21) and before the first frost (around November 12). Best results when soil holds above 50°F.

What growing zone is Miller County, AR for Coreopsis?

Miller County sits in USDA Zone 8b. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Miller County's climate?

Yes — Coreopsis grows well in Miller County's temperate climate. Miller County averages a 236-day frost-free season, with last frost around March 21 and first frost around November 12.

🌱

Your Miller County Garden Planner — Free

A 22-page printable planner built for Miller County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Miller County, AR. 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.