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When to plant Coreopsis in Weldon, CA

Coreopsis planted in Weldon between February 7 and February 28 matures in 60–80 days — well before the November 29 first frost.

When to Plant Coreopsis in Weldon, CA

Kern County, California Zone 9b July

Your July gardening checklist

Each item below is timed to Kern County, California's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost February 28
Avg. first frost November 29
Soil temp (4") 93°F
Watering Critical
Pest pressure High
Daylight 14.2 hrs
  1. Start harvesting coreopsis

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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.

Weldon, California is in USDA Zone 9b. The average last spring frost is February 28 and the first fall frost is November 29, giving you a growing season of approximately 274 days.

At an elevation of 389 feet, Kern County receives approximately 16.9 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Coreopsis may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Coreopsis successfully. Mulch heavily to conserve soil moisture.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Weldon, CA (Zone 9b) Year-round
274 days
Last Spring Frost February 28
274 growing days
First Fall Frost November 29

Weldon Soil Profile

Soil Type

Loam

Soil pH

6.2-7.7

Drainage

Well Drained

Coreopsis Planting Risk Windows

Early Start (70% safe) ✓ Fits season (78 days to spare)
Start indoors: Dec 26 Transplant: Feb 6 🌸 Bloom: Apr 3 – Sep 4
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Jan 3 Transplant: Feb 14 🌸 Bloom: Apr 11 – Sep 12
Safe Start (90%) ✓ Fits season (60 days to spare)
Start indoors: Feb 10 Transplant: Mar 24 🌸 Bloom: May 19 – Oct 20

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 Weldon

How your county's soil matches Coreopsis's growing requirements.

Soil pH

Your soil pH (6.2–7.7) overlaps with Coreopsis's range (5.5–7.5), though not a perfect match.

Soil Texture

The loam soil in Kern 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 (2.3%). Annual compost additions will help Coreopsis.

How to Plant Coreopsis

0.1"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Coreopsis

5
successive plantings in your 274-day season

Sow every 6.9 weeks. Last sowing by Sep 10 to harvest before frost.

Coreopsis Water Budget

Plant needs
0.5″/week
Rainfall provides
0.3″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,151 gal / 100 sq ft
Drought risk

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 3.9" 0" ❄️ Dormant
Feb 2.2" 3.4" 0" ✅ Rainfall sufficient
Mar 2.2" 2.4" 0" ✅ Rainfall sufficient
Apr 2.2" 1.2" 1" 💧 Light watering
May 2.2" 0.5" 1.7" 🚿 Regular watering
Jun 2.2" 0.1" 2.1" 🚿 Regular watering
Jul 2.2" 0" 2.2" 🚿 Regular watering
Aug 2.2" 0" 2.2" 🚿 Regular watering
Sep 2.2" 0.2" 2" 🚿 Regular watering
Oct 2.2" 0.7" 1.5" 🚿 Regular watering
Nov 2.2" 1.7" 0.5" 💧 Light watering
Dec 2.8" 0" ❄️ Dormant

Water needs are for active growing months only (Feb–Nov in Kern 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 needs ~1,855 GDD — county provides 7,287 GDD Excellent fit

Coreopsis Planting Timeline — Weldon, CA

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors January 3 Jan 3 – Jan 17
Transplant Outdoors February 14 Feb 14 – Feb 28
Direct Sow February 7 Feb 7 – Feb 28
Bloom April 11 Apr 11 – Sep 12

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · 1-2 times/week

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 5.5–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

274 days in Kern County

Growing Tips for Coreopsis in Weldon

Direct sow Coreopsis outdoors after February 28 in Kern County when soil has warmed and frost danger has passed.

With summer highs reaching 102°F in Kern 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.

Kern County receives only 17" of rain annually. Coreopsis needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 →

When should I plant Coreopsis in Weldon, CA?

In Weldon, CA, plant Coreopsis after the last frost (around February 28) and before the first frost (around November 29). Best results when soil holds above 50°F.

What growing zone is Weldon, CA for Coreopsis?

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

Can Coreopsis grow in Weldon's climate?

Yes — Coreopsis grows well in Weldon's temperate climate. Weldon averages a 275-day frost-free season, with last frost around February 28 and first frost around November 29.

🌱

Your Kern County Garden Planner — Free

A 22-page printable planner built for Kern 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 Kern County, CA. Local conditions may vary. Last updated: July 2026.