Blog

When to Plant Elderberries in Thurston County, WA

Thurston County, Washington Zone 8b May

Your May gardening checklist

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

Avg. last frost April 15
Avg. first frost October 29
Soil temp (4") 70°F
Watering High
Pest pressure High
Daylight 14.8 hrs
  1. Harden off and plant elderberries

    Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.

Instant PDF download. No spam, unsubscribe any time.

Elderberries are fast-growing shrubs or small trees producing clusters of small, dark berries used for syrups, wines, and immune-boosting preparations. The flowers are also edible.

Thurston County, Washington is in USDA Zone 8b. The average last spring frost is April 15 and the first fall frost is October 29, giving you a growing season of approximately 197 days.

At an elevation of 213 feet, Thurston County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Elderberries during the growing season.

Thurston County, WA (Zone 8b) Moderate season
197 days
Last Spring Frost April 15
197 growing days
First Fall Frost October 29

Thurston County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 27
Recommended (50%) ✓ Fits season
Transplant: May 6
Safe Start (90%) ✓ Fits season
Transplant: May 30

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 Thurston County

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

Soil pH

Your soil pH (5.3–6.6) overlaps with Elderberries's range (5.5–6.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.6%) — Elderberries will thrive.

How to Plant Elderberries

120"
Between Plants
144"
Between Rows

Plant Water Budget

Plant needs
0.8″/week
Rainfall provides
0.8″/week
Watering frequency Only during dry spells
Season total 8 gal / 100 sq ft

Monthly Watering Guide for Elderberries

Elderberries needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.

Month Elderberries Needs Rainfall You Supplement Action
Jan 4.9" 0" ❄️ Dormant
Feb 4.6" 0" ❄️ Dormant
Mar 4.2" 0" ❄️ Dormant
Apr 3.5" 2.7" 0.8" 💧 Light watering
May 3.5" 2.2" 1.3" 💧 Light watering
Jun 3.5" 1.4" 2.1" 🚿 Regular watering
Jul 3.5" 0.7" 2.8" 🚿 Regular watering
Aug 3.5" 0.7" 2.8" 🚿 Regular watering
Sep 3.5" 1.7" 1.8" 🚿 Regular watering
Oct 3.5" 3" 0.5" 💧 Light watering
Nov 5.3" 0" ❄️ Dormant
Dec 6" 0" ❄️ Dormant

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

Elderberries 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.

Elderberries needs ~15,284 GDD — county provides 3,299 GDD May not mature

Elderberries Planting Timeline — Thurston County, WA

Elderberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 6 May 6 – May 20

· 120" apart · Rows 144" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.8"/week · Only during dry spells

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 5.5–6.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

197 days in Thurston County

Growing Tips for Elderberries in Thurston County

Direct sow Elderberries outdoors after April 15 in Thurston County when soil has warmed and frost danger has passed.

Your 197.0-day growing season in Thurston County is tight for Elderberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Plant at least two varieties for cross-pollination. Prune annually to remove old canes and maintain shape. Berries must be cooked before eating as raw berries are mildly toxic.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Elderberries in Thurston County, WA?

Thurston County is in Zone 8b with an average last frost of April 15. Plan your Elderberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Thurston County, WA?

Thurston County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 15 and first fall frost is October 29.

🌱

Your Thurston County Garden Planner — Free

A 24-page printable planner built for Thurston County (Zone 8b). 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 Thurston 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.