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When to Plant Salvia in Walla Walla County, WA

Walla Walla County, Washington Zone 7a June

Your June planting checklist for Walla Walla County, Washington

Your garden in Walla Walla County, Washington is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 20
Avg. first frost October 15
Soil temp (4") 66°F
Watering Critical
Pest pressure High
Daylight 15.6 hrs
  1. Indoor seed-starting week for salvia

    Label every cell. You will absolutely forget which is which otherwise.

  2. Pick salvia

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Before July arrives, get these ready
  • First harvests: salvia

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Salvia splendens is a tender perennial from Brazil grown as a warm-season annual throughout the US. Its vivid, upright flower spikes in brilliant red, purple, and coral are irresistible to hummingbirds, bees, and butterflies. One of the longest-blooming annuals in the landscape — plants bloom from early summer until hard frost with minimal deadheading required.

Walla Walla County, Washington is in USDA Zone 7a. The average last spring frost is April 20 and the first fall frost is October 15, giving you a growing season of approximately 178 days.

At an elevation of 3,151 feet, Walla Walla County receives approximately 23.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Salvia during the growing season.

Annual Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Walla Walla County, WA (Zone 7a) Moderate season
178 days
Last Spring Frost April 20
178 growing days
First Fall Frost October 15

Walla Walla County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.4

Drainage

Well Drained

Salvia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Feb 6 Transplant: Apr 3 🌸 Bloom: Jun 12 – Oct 2
Recommended (50%) ✗ May not fit
Start indoors: Feb 23 Transplant: Apr 20 🌸 Bloom: Jun 29 – Oct 19
Safe Start (90%) ✗ May not fit
Start indoors: Mar 19 Transplant: May 14 🌸 Bloom: Jul 23 – Nov 12

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 Walla Walla County

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

Soil pH

Your soil pH (5.2–6.4) overlaps with Salvia's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — Salvia will thrive.

How to Plant Salvia

12"
Between Plants
18"
Between Rows

Succession Planting Salvia

2
successive plantings in your 178-day season

Sow every 8 weeks. Last sowing by Jul 17 to harvest before frost.

Salvia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 702 gal / 100 sq ft

Monthly Watering Guide for Salvia

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

Month Salvia Needs Rainfall You Supplement Action
Jan 2.9" 0" ❄️ Dormant
Feb 2.7" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 4.3" 1.7" 2.6" 🚿 Regular watering
May 4.3" 1.5" 2.8" 🚿 Regular watering
Jun 4.3" 1" 3.3" 🚿 Regular watering
Jul 4.3" 0.4" 3.9" 🚿 Regular watering
Aug 4.3" 0.5" 3.8" 🚿 Regular watering
Sep 4.3" 0.9" 3.4" 🚿 Regular watering
Oct 4.3" 2.2" 2.1" 💧 Light watering
Nov 3.7" 0" ❄️ Dormant
Dec 3.8" 0" ❄️ Dormant

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

Salvia 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.

Salvia needs ~1,100 GDD — county provides 2,447 GDD Excellent fit

Salvia Planting Timeline — Walla Walla County, WA

Salvia Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors April 20 Apr 20 – May 4
Bloom June 29 Jun 29 – Oct 19

· 12" apart · Rows 18" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

178 days in Walla Walla County

Growing Tips for Salvia in Walla Walla County

Direct sow Salvia outdoors after April 20 in Walla Walla County when soil has warmed and frost danger has passed.

Walla Walla County receives only 24" of rain annually. Salvia needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start indoors 8-10 weeks before last frost; seeds need 65-70°F soil and light to germinate (surface-sow, do not cover). Transplant after last frost when soil has warmed. Salvia is frost-sensitive — even a light frost kills plants. Pinch spent spikes to encourage continued bloom. Tolerates heat and humidity well once established. In zones 9b-11b can be grown as a short-lived perennial.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Salvia in Walla Walla County, WA?

Walla Walla County is in Zone 7a with an average last frost of April 20. Plan your Salvia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Walla Walla County, WA?

Walla Walla County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 20 and first fall frost is October 15.

🌱

Your Walla Walla County Garden Planner — Free

A 22-page printable planner built for Walla Walla 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 Walla Walla County, WA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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