When to plant Coreopsis in Greene County County,
Greene County County sits in USDA Zone 6a. Plant Coreopsis between April 20 (after last frost on April 13) and May 11.
When to Plant Coreopsis in Greene County, IL
June in the garden — Greene County, Illinois
Each item below is timed to Greene County, Illinois's frost dates and soil temperatures. Skip nothing, stress about nothing.
-
Fire up the seed-starting tray: coreopsis
Label every cell. You will absolutely forget which is which otherwise.
-
Basket week: coreopsis
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Looking ahead to July
- First harvests: coreopsis
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.
Greene County, Illinois is in USDA Zone 6a. The average last spring frost is April 13 and the first fall frost is October 21, giving you a growing season of approximately 191 days.
At an elevation of 1,248 feet, Greene County receives approximately 37 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Coreopsis during the growing season.
Greene County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.7
Drainage
Well Drained
Coreopsis Planting Risk Windows
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 Greene County
How your county's soil matches Coreopsis's growing requirements.
Soil pH
Your soil pH (6.1–6.7) is within Coreopsis's preferred range (5.5–7.5).
Soil Texture
The silt loam soil in Greene County is excellent for Coreopsis — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Coreopsis.
Organic Matter
Organic matter is excellent (4.5%) — Coreopsis will thrive.
How to Plant Coreopsis
Succession Planting Coreopsis
Sow every 6.9 weeks. Last sowing by Aug 02 to harvest before frost.
Coreopsis Water Budget
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Greene 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 Planting Timeline — Greene County, IL
Coreopsis Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 9 | Feb 9 – Feb 23 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 20 | Apr 20 – May 11 |
| Bloom | June 29 | Jun 29 – Oct 19 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| 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: ideal
🗺️ USDA Zone
Zone 6a
📆 Growing Season
191 days in Greene County
Growing Tips for Coreopsis in Greene County
Direct sow Coreopsis outdoors after April 13 in Greene 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 →
Coreopsis in Other Locations
Frequently Asked Questions
When should I plant Coreopsis in Greene County, IL?
Greene County is in Zone 6a with an average last frost of April 13. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.
What planting zone is Greene County, IL?
Greene County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 13 and first fall frost is October 21.
When should I plant Coreopsis in Greene County County, ?
In Greene County County, , plant Coreopsis after the last frost (around April 13) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Greene County County, for Coreopsis?
Greene County County sits in USDA Zone 6a. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.
Can Coreopsis grow in Greene County County's climate?
Yes — Coreopsis grows well in Greene County County's temperate climate. Greene County County averages a 191-day frost-free season, with last frost around April 13 and first frost around October 21.
Your Greene County Garden Planner — Free
A 22-page printable planner built for Greene County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.