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When to Plant Sweet Pea in Lincoln County, WA

Lincoln County, Washington Zone 6b June

What to do in June

Your Lincoln County, Washington garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost May 19
Avg. first frost September 26
Soil temp (4") 67°F
Watering Critical
Pest pressure High
Daylight 15.8 hrs
  1. Fire up the seed-starting tray: sweet pea

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

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Sweet peas (Lathyrus odoratus) are beloved cool-season climbing annuals grown primarily for their intensely fragrant, ruffled blooms in shades of pink, purple, red, and white. They thrive in cool spring conditions, climbing trellises to 4–6 feet, and make outstanding cut flowers. Bloom ceases once summer heat arrives, making early sowing critical for a long cutting season.

Lincoln County, Washington is in USDA Zone 6b. The average last spring frost is May 19 and the first fall frost is September 26, giving you a growing season of approximately 130 days.

At an elevation of 2,955 feet, Lincoln County receives approximately 21.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Sweet Pea during the growing season.

Annual Blooms in Spring Pollinator-friendly Good for cutting Fragrant
Lincoln County, WA (Zone 6b) Short season
130 days
Last Spring Frost May 19
130 growing days
First Fall Frost September 26

Lincoln County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.6

Drainage

Well Drained

Sweet Pea Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 27 Transplant: May 8 🌸 Bloom: Jul 24 – Oct 2
Recommended (50%) ✗ May not fit
Start indoors: Apr 7 Transplant: May 19 🌸 Bloom: Aug 4 – Oct 13
Safe Start (90%) ✗ May not fit
Start indoors: May 5 Transplant: Jun 16 🌸 Bloom: Sep 1 – Nov 10

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 Lincoln County

How your county's soil matches Sweet Pea's growing requirements.

Soil pH

Your soil pH (5.5–6.6) is more acidic than Sweet Pea prefers (7.0–7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Sweet Pea.

Organic Matter

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

How to Plant Sweet Pea

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Succession Planting Sweet Pea

2
successive plantings in your 130-day season

Sow every 7.4 weeks. Last sowing by Jul 03 to harvest before frost.

Sweet Pea Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 700 gal / 100 sq ft

Monthly Watering Guide for Sweet Pea

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

Month Sweet Pea Needs Rainfall You Supplement Action
Jan 3.2" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 4.3" 1.1" 3.2" 🚿 Regular watering
Jun 4.3" 1" 3.3" 🚿 Regular watering
Jul 4.3" 0.3" 4" 🚿 Regular watering
Aug 4.3" 0.5" 3.8" 🚿 Regular watering
Sep 4.3" 0.8" 3.5" 🚿 Regular watering
Oct 1.6" 0" ❄️ Dormant
Nov 3" 0" ❄️ Dormant
Dec 3.4" 0" ❄️ Dormant

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

Sweet Pea 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.

Sweet Pea needs ~1,144 GDD — county provides 1,982 GDD Excellent fit

Sweet Pea Planting Timeline — Lincoln County, WA

Sweet Pea Planting Calendar

Activity When Date Range
Start Indoors April 7 Apr 7 – Apr 21
Transplant Outdoors May 19 May 19 – Jun 2
Direct Sow April 14 Apr 14 – May 5
Bloom August 4 Aug 4 – Oct 13

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Transplant Outdoors
July
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

65–85 days

🧪 Soil pH

Needs 7–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 6b

📆 Growing Season

130 days in Lincoln County

Growing Tips for Sweet Pea in Lincoln County

Direct sow Sweet Pea outdoors after May 19 in Lincoln County when soil has warmed and frost danger has passed.

Common pests for Sweet Pea in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

Lincoln County receives only 22" of rain annually. Sweet Pea needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Soak seeds 24 hours before sowing to soften the hard seed coat; nick the seed coat with a file for the fastest germination. In cold zones (2–6), direct-sow as soon as soil can be worked, 4–6 weeks before last frost; seedlings tolerate light frost but not a hard freeze. In zones 7–9, fall-sow 8–10 weeks before first frost for earlier, stronger spring bloom. Provide a trellis or netting from the start. Feed with low-nitrogen, high-potassium fertilizer once buds form. Pick blooms regularly — even one mature seed pod stops flower production. All plant parts are mildly toxic if eaten.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Pea in Lincoln County, WA?

Lincoln County is in Zone 6b with an average last frost of May 19. Plan your Sweet Pea planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lincoln County, WA?

Lincoln County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is May 19 and first fall frost is September 26.

🌱

Your Lincoln County Garden Planner — Free

A 22-page printable planner built for Lincoln County (Zone 6b). 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 Lincoln 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.