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When to plant Coreopsis in Canyon County, ID

In Canyon County, plant Coreopsis in spring between May 4 and May 25, once soil temps hold above 50°F. Canyon County's last frost averages May 4, so most warm-season crops establish quickly once soil holds above 60°F. For a fall crop, sow between and — roughly 60–80 days before the first frost on October 10.

When to Plant Coreopsis in Canyon County, ID

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.

Canyon County, Idaho is in USDA Zone 7a. The average last spring frost is May 4 and the first fall frost is October 10, giving you a growing season of approximately 159 days.

At an elevation of 4,953 feet, Canyon County receives approximately 13.3 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Coreopsis during the growing season. 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
Canyon County, ID (Zone 7a) Moderate season
159 days
Last Spring Frost May 4
159 growing days
First Fall Frost October 10

Canyon County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.2

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 0.8" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 1.6" 0" ❄️ Dormant
May 4.3" 1.4" 2.9" 🚿 Regular watering
Jun 4.3" 1.1" 3.2" 🚿 Regular watering
Jul 4.3" 1" 3.3" 🚿 Regular watering
Aug 4.3" 1.6" 2.7" 🚿 Regular watering
Sep 4.3" 1" 3.3" 🚿 Regular watering
Oct 4.3" 1.1" 3.2" 🚿 Regular watering
Nov 1" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

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

Coreopsis Planting Timeline — Canyon County, ID

Coreopsis Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 – Mar 16
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Bloom July 13 Jul 13 – Nov 23

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April
May Transplant Outdoors Direct Sow
June
July Bloom
August Bloom
September Bloom
October Bloom
November Bloom
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 7a

📆 Growing Season

159 days in Canyon County

Growing Tips for Canyon County

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 →

Frequently Asked Questions

When should I plant Coreopsis in Canyon County, ID?

Canyon County is in Zone 7a with an average last frost of May 4. Plan your Coreopsis planting based on this frost date — see the calendar above for exact timing.

What planting zone is Canyon County, ID?

Canyon County, Idaho is in USDA Hardiness Zone 7a. The average last spring frost is May 4 and first fall frost is October 10.

When should I plant Coreopsis in Canyon County, ID?

In Canyon County, ID, plant Coreopsis after the last frost (around May 4) and before the first frost (around October 10). Best results when soil holds above 50°F.

What growing zone is Canyon County, ID for Coreopsis?

Canyon County sits in USDA Zone 7a. Coreopsis grows reliably in zones 3a through 9b, so it's a good fit here.

Can Coreopsis grow in Canyon County's climate?

Yes — Coreopsis grows well in Canyon County's temperate climate. Canyon County averages a 159-day frost-free season, with last frost around May 4 and first frost around October 10.

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Your Canyon County Garden Planner — Free

A 22-page printable planner built for Canyon County (Zone 7a). 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 Canyon County, ID. Local conditions may vary. Last updated: June 2026.

Sources & credits

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