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When to Plant Borage in Yakima County, WA

Yakima County, Washington Zone 7a May

Top priorities for Yakima County, Washington gardeners in May

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

Avg. last frost May 6
Avg. first frost October 3
Soil temp (4") 54°F
Watering Critical
Pest pressure Low
Daylight 14.8 hrs
Looking ahead to June
  • Starting indoors: borage
  • First harvests: borage

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Borage is a self-seeding annual herb with star-shaped blue flowers that attract pollinators. Its leaves have a cucumber-like flavor and the flowers are edible.

Yakima County, Washington is in USDA Zone 7a. The average last spring frost is May 6 and the first fall frost is October 3, giving you a growing season of approximately 150 days.

At an elevation of 3,150 feet, Yakima County receives approximately 18 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Borage during the growing season. With low rainfall, drip irrigation is essential for growing Borage successfully. Mulch heavily to conserve soil moisture.

Yakima County, WA (Zone 7a) Moderate season
150 days
Last Spring Frost May 6
150 growing days
First Fall Frost October 3

Yakima County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (52 days to spare)
Start indoors: Mar 26 Transplant: Apr 23 🍅 Harvest: Jun 18 – Aug 6
Recommended (50%) ✓ Fits season (52 days to spare)
Start indoors: Apr 1 Transplant: Apr 29 🍅 Harvest: Jun 24 – Aug 12
Safe Start (90%) ✓ Fits season (49 days to spare)
Start indoors: Apr 21 Transplant: May 19 🍅 Harvest: Jul 14 – Sep 1

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 Yakima County

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

Soil pH

Your soil pH (5.5–6.3) is more acidic than Borage prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) — Borage will thrive.

How to Plant Borage

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Borage

3
successive plantings in your 150-day season

Sow every 5.7 weeks. Last sowing by Aug 04 to harvest before frost.

For a dedicated fall crop, sow by Jul 25.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Borage

Borage needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Borage Needs Rainfall You Supplement Action
Jan 2.6" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 1.6" 0" ❄️ Dormant
Apr 1.3" 0" ❄️ Dormant
May 2.2" 1" 1.2" 🚿 Regular watering
Jun 2.2" 0.6" 1.6" 🚿 Regular watering
Jul 2.2" 0.3" 1.9" 🚿 Regular watering
Aug 2.2" 0.3" 1.9" 🚿 Regular watering
Sep 2.2" 0.6" 1.6" 🚿 Regular watering
Oct 2.2" 1.4" 0.8" 💧 Light watering
Nov 3.2" 0" ❄️ Dormant
Dec 3.1" 0" ❄️ Dormant

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

Borage 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.

Borage needs ~798 GDD — county provides 2,175 GDD Excellent fit

Borage Planting Timeline — Yakima County, WA

Borage Planting Calendar

Activity When Date Range
Start Indoors April 1 Apr 1 – Apr 15
Transplant Outdoors April 29 Apr 29 – May 13
Direct Sow April 22 Apr 22 – May 13
Harvest June 24 Jun 24 – Aug 12
Fall Sowing July 25 Jul 25 – Aug 8

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Fall Sowing Harvest
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

50–60 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

150 days in Yakima County

Growing Tips for Borage in Yakima County

Direct sow Borage outdoors after May 06 in Yakima County when soil has warmed and frost danger has passed.

General growing tips

Direct sow in spring as borage does not transplant well. Allow some plants to go to seed for next year. Young leaves are best; older leaves become bristly.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Borage in Yakima County, WA?

Yakima County is in Zone 7a with an average last frost of May 6. Plan your Borage planting based on this frost date — see the calendar above for exact timing.

What planting zone is Yakima County, WA?

Yakima County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is May 6 and first fall frost is October 3.

🌱

Your Yakima County Garden Planner — Free

A 24-page printable planner built for Yakima 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 Yakima 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.