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When to Plant Coreopsis in Grimes County, TX

Grimes County, Texas Zone 9a June

June to-do list for Grimes County, Texas

Each item below is timed to Grimes County, Texas's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost February 25
Avg. first frost December 1
Soil temp (4") 82°F
Watering Low
Pest pressure High
Daylight 14 hrs
  1. Bring in the coreopsis

    If you can't use it all right away, check the food-preservation section of your planner.

A few tasks this June that'll pay off in 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.

Grimes County, Texas is in USDA Zone 9a. The average last spring frost is February 25 and the first fall frost is December 1, giving you a growing season of approximately 279 days.

At an elevation of 33 feet, Grimes County receives approximately 65.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91°F, providing good warmth for Coreopsis during the growing season. 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
Grimes County, TX (Zone 9a) Year-round
279 days
Last Spring Frost February 25
279 growing days
First Fall Frost December 1

Grimes County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.8-6.5

Drainage

Well Drained

Coreopsis Planting Risk Windows

Early Start (70% safe) ✓ Fits season (87 days to spare)
Start indoors: Dec 18 Transplant: Jan 29 🌸 Bloom: Mar 26 – Aug 27
Recommended (50%) ✓ Fits season (83 days to spare)
Start indoors: Dec 31 Transplant: Feb 11 🌸 Bloom: Apr 8 – Sep 9
Safe Start (90%) ✓ Fits season (86 days to spare)
Start indoors: Jan 14 Transplant: Feb 25 🌸 Bloom: Apr 22 – Sep 23

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 Grimes County

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

Soil pH

Your soil pH (5.8–6.5) is within Coreopsis's preferred range (5.5–7.5).

Soil Texture

Sandy soil in Grimes 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 279-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
1.0″/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 1.9" 0" ❄️ Dormant
Feb 2.2" 2.1" 0.1" 💧 Light watering
Mar 2.2" 4.7" 0" ✅ Rainfall sufficient
Apr 2.2" 6" 0" ✅ Rainfall sufficient
May 2.2" 9.9" 0" ✅ Rainfall sufficient
Jun 2.2" 9.9" 0" ✅ Rainfall sufficient
Jul 2.2" 8.3" 0" ✅ Rainfall sufficient
Aug 2.2" 8.3" 0" ✅ Rainfall sufficient
Sep 2.2" 6.6" 0" ✅ Rainfall sufficient
Oct 2.2" 3.9" 0" ✅ Rainfall sufficient
Nov 2.2" 2" 0.2" 💧 Light watering
Dec 2.2" 1.7" 0.5" 💧 Light watering

Water needs are for active growing months only (Feb–Dec in Grimes 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 ~1,278 GDD — county provides 5,110 GDD Excellent fit

Coreopsis Planting Timeline — Grimes County, TX

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors December 31 Dec 31 – Jan 14
Transplant Outdoors February 11 Feb 11 – Feb 25
Direct Sow February 11 Feb 11 – Mar 4
Bloom April 8 Apr 8 – Sep 9

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 9a

📆 Growing Season

279 days in Grimes County

Growing Tips for Coreopsis in Grimes County

Direct sow Coreopsis outdoors after February 25 in Grimes County when soil has warmed and frost danger has passed.

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

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 Grimes County, TX?

Grimes County is in Zone 9a with an average last frost of February 25. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Grimes County, TX?

Grimes County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 25 and first fall frost is December 1.

🌱

Your Grimes County Garden Planner — Free

A 22-page printable planner built for Grimes 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 Grimes County, TX. 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.