When to plant Coreopsis in Butte County, CA
For Coreopsis in Butte County, the safe spring window opens around March 30 and closes around April 20. Last expected frost is April 20, first fall frost November 10, giving a 204-day growing season.
When to Plant Coreopsis in Butte County, CA
What to do in July
Your Butte County, California garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.
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Basket week: coreopsis
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
A few tasks this July that'll pay off in August
- 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.
Butte County, California is in USDA Zone 9b. The average last spring frost is April 20 and the first fall frost is November 10, giving you a growing season of approximately 204 days.
At an elevation of 144 feet, Butte County receives approximately 44.8 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Coreopsis during the growing season.
Butte County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.7
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 Butte County
How your county's soil matches Coreopsis's growing requirements.
Soil pH
Your soil pH (6.8–7.7) overlaps with Coreopsis's range (5.5–7.5), though not a perfect match.
Soil Texture
The loam soil in Butte County is excellent for Coreopsis — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Coreopsis.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Coreopsis.
How to Plant Coreopsis
Succession Planting Coreopsis
Sow every 6.9 weeks. Last sowing by Aug 22 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 | — | 9.7" | 0" | ❄️ Dormant |
| Feb | — | 9.9" | 0" | ❄️ Dormant |
| Mar | — | 6.9" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 1.1" | 1.1" | 🚿 Regular watering |
| Jun | 2.2" | 0.2" | 2" | 🚿 Regular watering |
| Jul | 2.2" | 0" | 2.2" | 🚿 Regular watering |
| Aug | 2.2" | 0" | 2.2" | 🚿 Regular watering |
| Sep | 2.2" | 0.4" | 1.8" | 🚿 Regular watering |
| Oct | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Nov | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Dec | — | 7.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Butte 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 — Butte County, CA
Coreopsis Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Direct Sow | March 30 | Mar 30 – Apr 20 |
| Bloom | June 1 | Jun 1 – Nov 2 |
Plant 0.1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| 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: acceptable
🗺️ USDA Zone
Zone 9b
📆 Growing Season
204 days in Butte County
Growing Tips for Coreopsis in Butte County
Direct sow Coreopsis outdoors after April 20 in Butte 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 Butte County, CA?
Butte County is in Zone 9b with an average last frost of April 20. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.
What planting zone is Butte County, CA?
Butte County, California is in USDA Hardiness Zone 9b. The average last spring frost is April 20 and first fall frost is November 10.
When should I plant Coreopsis in Butte County, CA?
In Butte County, CA, plant Coreopsis after the last frost (around April 20) and before the first frost (around November 10). Best results when soil holds above 50°F.
What growing zone is Butte County, CA for Coreopsis?
Butte County sits in USDA Zone 9b. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.
Can Coreopsis grow in Butte County's climate?
Yes — Coreopsis grows well in Butte County's temperate climate. Butte County averages a 204-day frost-free season, with last frost around April 20 and first frost around November 10.
Your Butte County Garden Planner — Free
A 22-page printable planner built for Butte County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.