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When to Plant Salvia in Cowlitz County, WA

Cowlitz County, Washington Zone 8b June

Top priorities for Cowlitz County, Washington gardeners in June

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

Avg. last frost April 15
Avg. first frost October 29
Soil temp (4") 82°F
Watering High
Pest pressure High
Daylight 15.6 hrs
  1. Sow salvia in trays indoors

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. Start harvesting salvia

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

To set up a strong July, finish these tasks
  • 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.

Cowlitz 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 268 feet, Cowlitz County receives approximately 47.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Salvia during the growing season.

Annual Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting Fragrant
Cowlitz County, WA (Zone 8b) Moderate season
197 days
Last Spring Frost April 15
197 growing days
First Fall Frost October 29

Cowlitz County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.5

Drainage

Well Drained

Salvia Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 12 Transplant: Mar 26 🌸 Bloom: Jun 4 – Nov 5
Recommended (50%) ✗ May not fit
Start indoors: Feb 18 Transplant: Apr 1 🌸 Bloom: Jun 10 – Nov 11
Safe Start (90%) ✗ May not fit
Start indoors: Mar 12 Transplant: Apr 23 🌸 Bloom: Jul 2 – Dec 3

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 Cowlitz County

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

Soil pH

Your soil pH (5.7–6.5) is within Salvia's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) — Salvia will thrive.

How to Plant Salvia

12"
Between Plants
18"
Between Rows

Succession Planting Salvia

3
successive plantings in your 197-day season

Sow every 8 weeks. Last sowing by Jul 31 to harvest before frost.

Salvia Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 7.2" 0" ❄️ Dormant
Feb 4.6" 0" ❄️ Dormant
Mar 5.1" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 2.9" 1.4" 💧 Light watering
Jun 4.3" 2" 2.3" 🚿 Regular watering
Jul 4.3" 0.8" 3.5" 🚿 Regular watering
Aug 4.3" 0.9" 3.4" 🚿 Regular watering
Sep 4.3" 1.6" 2.7" 🚿 Regular watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 7.6" 0" ❄️ Dormant
Dec 7.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cowlitz 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 ~1,220 GDD — county provides 3,004 GDD Excellent fit

Salvia Planting Timeline — Cowlitz County, WA

Salvia Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors April 1 Apr 1 – Apr 15
Bloom June 10 Jun 10 – Nov 11

· 12" apart · Rows 18" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 8b

📆 Growing Season

197 days in Cowlitz County

Growing Tips for Salvia in Cowlitz County

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

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 Cowlitz County, WA?

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

What planting zone is Cowlitz County, WA?

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

🌱

Your Cowlitz County Garden Planner — Free

A 22-page printable planner built for Cowlitz 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.

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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 Cowlitz 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.