When to plant Coreopsis in Tazewell County, IL
For Coreopsis in Tazewell County, the safe spring window opens around April 26 and closes around May 17. Last expected frost is April 19, first fall frost October 15, giving a 179-day growing season.
When to Plant Coreopsis in Tazewell County, IL
June in the garden — Tazewell County, Illinois
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Tazewell County, Illinois.
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Fire up the seed-starting tray: coreopsis
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
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.
Tazewell County, Illinois is in USDA Zone 6a. The average last spring frost is April 19 and the first fall frost is October 15, giving you a growing season of approximately 179 days.
At an elevation of 1,006 feet, Tazewell County receives approximately 40 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Coreopsis during the growing season.
Tazewell County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-6.9
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 Tazewell County
How your county's soil matches Coreopsis's growing requirements.
Soil pH
Your soil pH (6.3–6.9) is within Coreopsis's preferred range (5.5–7.5).
Soil Texture
The silt loam soil in Tazewell County is excellent for Coreopsis — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.0%) — Coreopsis will thrive.
How to Plant Coreopsis
Succession Planting Coreopsis
Sow every 6.9 weeks. Last sowing by Jul 27 to harvest before frost.
Coreopsis Water Budget
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 | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.6" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5.1" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Tazewell 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 — Tazewell County, IL
Coreopsis Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 15 | Feb 15 – Mar 1 |
| Transplant Outdoors | April 26 | Apr 26 – May 10 |
| Direct Sow | April 26 | Apr 26 – May 17 |
| Bloom | July 5 | Jul 5 – Oct 25 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| 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
179 days in Tazewell County
Growing Tips for Coreopsis in Tazewell County
Direct sow Coreopsis outdoors after April 19 in Tazewell 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 Tazewell County, IL?
Tazewell County is in Zone 6a with an average last frost of April 19. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.
What planting zone is Tazewell County, IL?
Tazewell County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 19 and first fall frost is October 15.
When should I plant Coreopsis in Tazewell County, IL?
In Tazewell County, IL, plant Coreopsis after the last frost (around April 19) and before the first frost (around October 15). Best results when soil holds above 50°F.
What growing zone is Tazewell County, IL for Coreopsis?
Tazewell 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 Tazewell County's climate?
Yes — Coreopsis grows well in Tazewell County's temperate climate. Tazewell County averages a 179-day frost-free season, with last frost around April 19 and first frost around October 15.
Your Tazewell County Garden Planner — Free
A 22-page printable planner built for Tazewell 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.