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When to plant Coreopsis in Comptche, CA

Comptche sits in USDA Zone 9b. Plant Coreopsis between March 2 (after last frost on March 23) and March 23.

When to Plant Coreopsis in Comptche, CA

Mendocino County, California Zone 9b July

Top priorities for Mendocino County, California gardeners in July

July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Mendocino County, California.

Avg. last frost March 23
Avg. first frost November 9
Soil temp (4") 88°F
Watering Critical
Pest pressure High
Daylight 14.5 hrs
  1. Start harvesting coreopsis

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Before August arrives, get these ready
  • 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.

Comptche, California is in USDA Zone 9b. The average last spring frost is March 23 and the first fall frost is November 9, giving you a growing season of approximately 231 days.

At an elevation of 180 feet, Mendocino County receives approximately 24 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 87°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.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Comptche, CA (Zone 9b) Long season
231 days
Last Spring Frost March 23
231 growing days
First Fall Frost November 9

Comptche Soil Profile

Soil Type

Sandy Loam

Soil pH

6.1-7.2

Drainage

Well Drained

Monthly Watering Guide for Coreopsis

Coreopsis needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Coreopsis Needs Rainfall You Supplement Action
Jan 5.2" 0" ❄️ Dormant
Feb 4.6" 0" ❄️ Dormant
Mar 4.3" 3.7" 0.6" 💧 Light watering
Apr 4.3" 1.9" 2.4" 🚿 Regular watering
May 4.3" 0.6" 3.7" 🚿 Regular watering
Jun 4.3" 0.2" 4.1" 🚿 Regular watering
Jul 4.3" 0" 4.3" 🚿 Regular watering
Aug 4.3" 0" 4.3" 🚿 Regular watering
Sep 4.3" 0.2" 4.1" 🚿 Regular watering
Oct 4.3" 1" 3.3" 🚿 Regular watering
Nov 4.3" 2.6" 1.7" 💧 Light watering
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Mendocino County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Coreopsis Planting Timeline — Comptche, CA

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors January 26 Jan 26 – Feb 9
Transplant Outdoors March 9 Mar 9 – Mar 23
Direct Sow March 2 Mar 2 – Mar 23
Bloom May 4 May 4 – Oct 5

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March Transplant Outdoors Direct Sow
April
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 9b

📆 Growing Season

231 days in Mendocino County

Growing Tips for Comptche

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 →

When should I plant Coreopsis in Comptche, CA?

In Comptche, CA, plant Coreopsis after the last frost (around March 23) and before the first frost (around November 9). Best results when soil holds above 50°F.

What growing zone is Comptche, CA for Coreopsis?

Comptche sits in USDA Zone 9b. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Comptche's climate?

Yes — Coreopsis grows well in Comptche's temperate climate. Comptche averages a 231-day frost-free season, with last frost around March 23 and first frost around November 9.

🌱

Your Mendocino County Garden Planner — Free

A 22-page printable planner built for Mendocino 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.

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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 Mendocino County, CA. Local conditions may vary. Last updated: July 2026.