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When to plant Coreopsis in Washington County County,

Plant Coreopsis in Washington County County from February 19 to March 12 in spring. Washington County County sits in USDA Zone 9a, with last frost around March 5 and first frost on November 20.

When to Plant Coreopsis in Washington County, FL

Washington County, Florida Zone 9a June

Your June gardening checklist

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Washington County, Florida.

Avg. last frost March 5
Avg. first frost November 20
Soil temp (4") 83°F
Watering Low
Pest pressure High
Daylight 14 hrs
  1. Pick coreopsis

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

July will be here before you know it — start on
  • 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.

Washington County, Florida is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 20, giving you a growing season of approximately 260 days.

At an elevation of 196 feet, Washington County receives approximately 50.6 inches of rainfall annually with predominantly sand soil. Summer highs average 97°F, so Coreopsis may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Coreopsis will need more frequent watering and organic matter to retain nutrients. 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
Washington County, FL (Zone 9a) Long season
260 days
Last Spring Frost March 5
260 growing days
First Fall Frost November 20

Washington County Soil Profile

Soil Type

Sand

Soil pH

4.8-5.9

Drainage

Well Drained

Coreopsis Planting Risk Windows

Early Start (70% safe) ✓ Fits season (66 days to spare)
Start indoors: Dec 29 Transplant: Feb 9 🌸 Bloom: Apr 6 – Sep 7
Recommended (50%) ✓ Fits season (64 days to spare)
Start indoors: Jan 8 Transplant: Feb 19 🌸 Bloom: Apr 16 – Sep 17
Safe Start (90%) ✓ Fits season (64 days to spare)
Start indoors: Jan 30 Transplant: Mar 13 🌸 Bloom: May 8 – Oct 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 Washington County

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

Soil pH

Your soil pH (4.8–5.9) is more acidic than Coreopsis prefers (5.5–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Washington County warms quickly in spring but drains fast. Coreopsis will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Coreopsis.

Organic Matter

Organic matter is low (1.7%). Add 2-3 inches of compost before planting Coreopsis.

How to Plant Coreopsis

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

Succession Planting Coreopsis

5
successive plantings in your 260-day season

Sow every 6.9 weeks. Last sowing by Sep 01 to harvest before frost.

Coreopsis Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/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 2" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 2.2" 2.5" 0" ✅ Rainfall sufficient
Apr 2.2" 2.2" 0" ✅ Rainfall sufficient
May 2.2" 3.7" 0" ✅ Rainfall sufficient
Jun 2.2" 6.8" 0" ✅ Rainfall sufficient
Jul 2.2" 8.5" 0" ✅ Rainfall sufficient
Aug 2.2" 6.5" 0" ✅ Rainfall sufficient
Sep 2.2" 7.3" 0" ✅ Rainfall sufficient
Oct 2.2" 4" 0" ✅ Rainfall sufficient
Nov 2.2" 2.1" 0.1" 💧 Light watering
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Washington 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 ~1,592 GDD — county provides 5,915 GDD Excellent fit

Coreopsis Planting Timeline — Washington County, FL

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors January 8 Jan 8 – Jan 22
Transplant Outdoors February 19 Feb 19 – Mar 5
Direct Sow February 19 Feb 19 – Mar 12
Bloom April 16 Apr 16 – Sep 17

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 9a

📆 Growing Season

260 days in Washington County

Growing Tips for Coreopsis in Washington County

Direct sow Coreopsis outdoors after March 05 in Washington County when soil has warmed and frost danger has passed.

Sandy soil in Washington County dries quickly — mulch Coreopsis with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 97°F in Washington County, provide afternoon shade for Coreopsis and water deeply in the morning.

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 Washington County, FL?

Washington County is in Zone 9a with an average last frost of March 5. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, FL?

Washington County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 20.

When should I plant Coreopsis in Washington County County, ?

In Washington County County, , plant Coreopsis after the last frost (around March 5) and before the first frost (around November 20). Best results when soil holds above 50°F.

What growing zone is Washington County County, for Coreopsis?

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

Can Coreopsis grow in Washington County County's climate?

Yes — Coreopsis grows well in Washington County County's temperate climate. Washington County County averages a 260-day frost-free season, with last frost around March 5 and first frost around November 20.

🌱

Your Washington County Garden Planner — Free

A 22-page printable planner built for Washington County (Zone 9a). 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 Washington County, FL. 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.