Blog

When to Plant Aronia in Asotin County, WA

Asotin County, Washington Zone 7a May

Your May planting checklist for Asotin County, Washington

A quick May briefing for Asotin County, Washington gardeners — what's urgent, what's next, and what can wait.

Avg. last frost May 9
Avg. first frost September 30
Soil temp (4") 59°F
Watering Critical
Pest pressure Low
Daylight 14.8 hrs
  1. Get aronia in the ground

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

Instant PDF download. No spam, unsubscribe any time.

Aronia (chokeberry) is an extremely hardy native shrub producing astringent dark berries rich in antioxidants. The berries are typically processed into juice, jam, or wine.

Asotin County, Washington is in USDA Zone 7a. The average last spring frost is May 9 and the first fall frost is September 30, giving you a growing season of approximately 144 days.

At an elevation of 2,029 feet, Asotin County receives approximately 14 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Aronia during the growing season. With low rainfall, drip irrigation is essential for growing Aronia successfully. Mulch heavily to conserve soil moisture.

Asotin County, WA (Zone 7a) Short season
144 days
Last Spring Frost May 9
144 growing days
First Fall Frost September 30

Asotin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 19
Recommended (50%) ✓ Fits season
Transplant: May 30
Safe Start (90%) ✓ Fits season
Transplant: Jun 27

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 Asotin County

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

Soil pH

Your soil pH (5.5–6.5) is within Aronia's preferred range (5.0–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — Aronia will thrive.

How to Plant Aronia

48"
Between Plants
72"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.4″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 758 gal / 100 sq ft

Monthly Watering Guide for Aronia

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

Month Aronia Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 0.9" 0" ❄️ Dormant
May 4.3" 0.8" 3.5" 🚿 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" 0.5" 3.8" 🚿 Regular watering
Oct 1.2" 0" ❄️ Dormant
Nov 2.4" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Aronia 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.

Aronia needs ~12,547 GDD — county provides 1,980 GDD May not mature

Aronia Planting Timeline — Asotin County, WA

Aronia Planting Calendar

Activity When Date Range
Transplant Outdoors May 30 May 30 – Jun 13

· 48" apart · Rows 72" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 7a

📆 Growing Season

144 days in Asotin County

Growing Tips for Aronia in Asotin County

Direct sow Aronia outdoors after May 09 in Asotin County when soil has warmed and frost danger has passed.

Your 144.0-day growing season in Asotin County is tight for Aronia (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

Asotin County receives only 14" of rain annually. Aronia needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Plant in full sun for best fruiting. Very adaptable to soil types. Minimal pest and disease problems. Harvest berries in fall when fully black. Suckers can be divided for propagation.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Aronia in Asotin County, WA?

Asotin County is in Zone 7a with an average last frost of May 9. Plan your Aronia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Asotin County, WA?

Asotin County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is May 9 and first fall frost is September 30.

🌱

Your Asotin County Garden Planner — Free

A 24-page printable planner built for Asotin 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.

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 Asotin County, WA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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