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When to plant Coreopsis in Nassau County County,

Nassau County County gardeners should plant Coreopsis between January 31 and February 21 in spring. With Nassau County County's Zone 9a climate (last frost February 14), Coreopsis needs 80 days to mature — plant by September 12 for a full harvest.

When to Plant Coreopsis in Nassau County, FL

Nassau County, Florida Zone 9a June

Your June game plan for Nassau County, Florida

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost February 14
Avg. first frost December 1
Soil temp (4") 85°F
Watering Low
Pest pressure High
Daylight 14 hrs
  1. Basket week: coreopsis

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

Looking ahead to July
  • 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.

Nassau County, Florida is in USDA Zone 9a. The average last spring frost is February 14 and the first fall frost is December 1, giving you a growing season of approximately 290 days.

At an elevation of 408 feet, Nassau County receives approximately 57.9 inches of rainfall annually with predominantly sand soil. Summer highs average 101°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
Nassau County, FL (Zone 9a) Year-round
290 days
Last Spring Frost February 14
290 growing days
First Fall Frost December 1

Nassau County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.8

Drainage

Well Drained

Coreopsis Planting Risk Windows

Early Start (70% safe) ✓ Fits season (92 days to spare)
Start indoors: Dec 13 Transplant: Jan 24 🌸 Bloom: Mar 21 – Aug 22
Recommended (50%) ✓ Fits season (94 days to spare)
Start indoors: Dec 20 Transplant: Jan 31 🌸 Bloom: Mar 28 – Aug 29
Safe Start (90%) ✓ Fits season (76 days to spare)
Start indoors: Jan 26 Transplant: Mar 9 🌸 Bloom: May 4 – Oct 5

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 Nassau County

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

Soil pH

Your soil pH (5.2–5.8) overlaps with Coreopsis's range (5.5–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is low (1.4%). 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 290-day season

Sow every 6.9 weeks. Last sowing by Sep 12 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 2.8" 0" ❄️ Dormant
Feb 2.2" 3.2" 0" ✅ Rainfall sufficient
Mar 2.2" 3.7" 0" ✅ Rainfall sufficient
Apr 2.2" 2.9" 0" ✅ Rainfall sufficient
May 2.2" 4.1" 0" ✅ Rainfall sufficient
Jun 2.2" 6.6" 0" ✅ Rainfall sufficient
Jul 2.2" 7.9" 0" ✅ Rainfall sufficient
Aug 2.2" 8.7" 0" ✅ Rainfall sufficient
Sep 2.2" 7.9" 0" ✅ Rainfall sufficient
Oct 2.2" 5.3" 0" ✅ Rainfall sufficient
Nov 2.2" 2.2" 0" ✅ Rainfall sufficient
Dec 2.2" 2.5" 0" ✅ Rainfall sufficient

Water needs are for active growing months only (Feb–Dec in Nassau 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 ~1,802 GDD — county provides 7,493 GDD Excellent fit

Coreopsis Planting Timeline — Nassau County, FL

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors December 20 Dec 20 – Jan 3
Transplant Outdoors January 31 Jan 31 – Feb 14
Direct Sow January 31 Jan 31 – Feb 21
Bloom March 28 Mar 28 – Aug 29

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

Month-by-Month Timeline

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

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 9a

📆 Growing Season

290 days in Nassau County

Growing Tips for Coreopsis in Nassau County

Direct sow Coreopsis outdoors after February 14 in Nassau County when soil has warmed and frost danger has passed.

Sandy soil in Nassau 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 101°F in Nassau 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 Nassau County, FL?

Nassau County is in Zone 9a with an average last frost of February 14. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Nassau County, FL?

Nassau County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is February 14 and first fall frost is December 1.

When should I plant Coreopsis in Nassau County, ?

In Nassau County, , plant Coreopsis after the last frost (around February 14) and before the first frost (around December 1). Best results when soil holds above 50°F.

What growing zone is Nassau County, for Coreopsis?

Nassau 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 Nassau County's climate?

Yes — Coreopsis grows well in Nassau County's temperate climate. Nassau County averages a 291-day frost-free season, with last frost around February 14 and first frost around December 1.

🌱

Your Nassau County Garden Planner — Free

A 22-page printable planner built for Nassau 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 Nassau 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.