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When to Plant Sunflower in Baker County, OR

Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.

Baker County, Oregon is in USDA Zone 6b. The average last spring frost is May 30 and the first fall frost is September 12, giving you a growing season of approximately 105 days.

At an elevation of 1,398 feet, Baker County receives approximately 16.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Sunflower during the growing season. With low rainfall, drip irrigation is essential for growing Sunflower successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Baker County, OR (Zone 6b) Short season
105 days
Last Spring Frost May 30
105 growing days
First Fall Frost September 12

Baker County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Monthly Watering Guide for Sunflower

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

Month Sunflower Needs Rainfall You Supplement Action
Jan 2.3" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 1.1" 0" ❄️ Dormant
May 4.3" 1.1" 3.2" 🚿 Regular watering
Jun 4.3" 0.6" 3.7" 🚿 Regular watering
Jul 4.3" 0.2" 4.1" 🚿 Regular watering
Aug 4.3" 0.3" 4" 🚿 Regular watering
Sep 4.3" 0.8" 3.5" 🚿 Regular watering
Oct 1.6" 0" ❄️ Dormant
Nov 2.5" 0" ❄️ Dormant
Dec 3.1" 0" ❄️ Dormant

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

Sunflower Planting Timeline — Baker County, OR

Sunflower Planting Calendar

Activity When Date Range
Start Indoors May 9 May 9 – May 23
Transplant Outdoors May 30 May 30 – Jun 13
Direct Sow May 30 May 30 – Jun 20
Bloom August 22 Aug 22 – Nov 21

Plant 1" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

105 days in Baker County

Growing Tips for Baker County

Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Pole_beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Baker County, OR?

Baker County is in Zone 6b with an average last frost of May 30. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.

What planting zone is Baker County, OR?

Baker County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is May 30 and first fall frost is September 12.

🌱

Your Baker County Garden Planner — Free

A 22-page printable planner built for Baker County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Baker County, OR. Local conditions may vary. Last updated: July 2026.

Sources & credits

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