When to Plant Coreopsis in Sterling County, TX
August in the garden — Sterling County, Texas
We've pulled the most time-sensitive tasks for Sterling County, Texas this August and put them front and centre. Tackle them in order.
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Collect coreopsis at their peak
If you can't use it all right away, check the food-preservation section of your planner.
Coming up in September — start thinking about
- 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.
Sterling County, Texas is in USDA Zone 8a. The average last spring frost is March 24 and the first fall frost is November 12, giving you a growing season of approximately 233 days.
At an elevation of 2,929 feet, Sterling County receives approximately 50.9 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°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.
Sterling County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.4-8.6
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 Sterling County
How your county's soil matches Coreopsis's growing requirements.
Soil pH
Your soil pH (7.4–8.6) is more alkaline than Coreopsis prefers (5.5–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Sterling 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 (0.9%). Add 2-3 inches of compost before planting Coreopsis.
How to Plant Coreopsis
Succession Planting Coreopsis
Sow every 6.9 weeks. Last sowing by Aug 24 to harvest before frost.
Coreopsis Water Budget
Water stress score is 8/10 — 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 | — | 3.5" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| May | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Jun | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Jul | 2.2" | 8.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 9.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 7.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Sterling 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 — Sterling County, TX
Coreopsis Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 27 | Jan 27 – Feb 10 |
| Transplant Outdoors | March 24 | Mar 24 – Apr 7 |
| Direct Sow | March 17 | Mar 17 – Apr 7 |
| Bloom | May 26 | May 26 – Oct 20 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Bloom |
| 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: too_alkaline
🗺️ USDA Zone
Zone 8a
📆 Growing Season
233 days in Sterling County
Growing Tips for Coreopsis in Sterling County
Direct sow Coreopsis outdoors after March 24 in Sterling County when soil has warmed and frost danger has passed.
Sandy soil in Sterling 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 99°F in Sterling 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 →
Coreopsis in Other Locations
Frequently Asked Questions
When should I plant Coreopsis in Sterling County, TX?
Sterling County is in Zone 8a with an average last frost of March 24. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sterling County, TX?
Sterling County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 24 and first fall frost is November 12.
Your Sterling County Garden Planner — Free
A 22-page printable planner built for Sterling County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.