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When to Plant Geraniums in Wallowa County, OR

Wallowa County, Oregon Zone 6b July

What to do in July

Your Wallowa County, Oregon garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.

Avg. last frost May 11
Avg. first frost September 22
Soil temp (4") 77°F
Watering Critical
Pest pressure High
Daylight 15.2 hrs
  1. Start geraniums under lights

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Bring in the geraniums

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

To set up a strong August, finish these tasks
  • First harvests: geraniums

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Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.

Wallowa County, Oregon is in USDA Zone 6b. The average last spring frost is May 11 and the first fall frost is September 22, giving you a growing season of approximately 134 days.

At an elevation of 1,240 feet, Wallowa County receives approximately 22.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Geraniums during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Wallowa County, OR (Zone 6b) Short season
134 days
Last Spring Frost May 11
134 growing days
First Fall Frost September 22

Wallowa County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.2

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 20 Transplant: May 8 🌸 Bloom: Jul 17 – Oct 23
Recommended (50%) ✗ May not fit
Start indoors: Mar 2 Transplant: May 18 🌸 Bloom: Jul 27 – Nov 2
Safe Start (90%) ✗ May not fit
Start indoors: Apr 3 Transplant: Jun 19 🌸 Bloom: Aug 28 – Dec 4

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 Wallowa County

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

Soil pH

Your soil pH (5.3–6.2) is more acidic than Geraniums prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Wallowa County is excellent for Geraniums — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Geraniums.

Organic Matter

Organic matter is excellent (5.4%) — Geraniums will thrive.

How to Plant Geraniums

0.1"
Planting Depth
12"
Between Plants
14"
Between Rows

Succession Planting Geraniums

2
successive plantings in your 134-day season

Sow every 8 weeks. Last sowing by Jun 14 to harvest before frost.

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 706 gal / 100 sq ft

Monthly Watering Guide for Geraniums

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

Month Geraniums Needs Rainfall You Supplement Action
Jan 2.9" 0" ❄️ Dormant
Feb 2.3" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 4.3" 1.3" 3" 🚿 Regular watering
Jun 4.3" 1" 3.3" 🚿 Regular watering
Jul 4.3" 0.4" 3.9" 🚿 Regular watering
Aug 4.3" 0.4" 3.9" 🚿 Regular watering
Sep 4.3" 1" 3.3" 🚿 Regular watering
Oct 2.1" 0" ❄️ Dormant
Nov 3.9" 0" ❄️ Dormant
Dec 3.6" 0" ❄️ Dormant

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

Geraniums 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.

Geraniums needs ~1,169 GDD — county provides 1,842 GDD Excellent fit

Geraniums Planting Timeline — Wallowa County, OR

Geraniums Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 – Mar 16
Transplant Outdoors May 18 May 18 – Jun 1
Bloom July 27 Jul 27 – Nov 2

Plant 0.1" deep · 12" apart · Rows 14" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 6b

📆 Growing Season

134 days in Wallowa County

Growing Tips for Geraniums in Wallowa County

Direct sow Geraniums outdoors after May 11 in Wallowa County when soil has warmed and frost danger has passed.

Wallowa County receives only 23" of rain annually. Geraniums needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Geraniums in Wallowa County, OR?

Wallowa County is in Zone 6b with an average last frost of May 11. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Wallowa County, OR?

Wallowa County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is May 11 and first fall frost is September 22.

🌱

Your Wallowa County Garden Planner — Free

A 22-page printable planner built for Wallowa 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.

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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 Wallowa County, OR. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.