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When to Plant Christmas Lima Beans in Washington County, ID

Washington County, Idaho Zone 7a May

Your May planting checklist for Washington County, Idaho

We've pulled the most time-sensitive tasks for Washington County, Idaho this May and put them front and centre. Tackle them in order.

Avg. last frost May 9
Avg. first frost October 1
Soil temp (4") 51°F
Watering High
Pest pressure Low
Daylight 14.6 hrs
  1. Set out christmas lima beans seedlings

    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.

  2. Plant christmas lima beans from seed, right in the garden

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

To set up a strong June, finish these tasks
  • Starting indoors: christmas lima beans

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Christmas lima beans are a large, beautifully marbled heirloom bean with a rich, chestnut-like flavor. They are a climbing variety that produces generously in warm weather.

Washington County, Idaho is in USDA Zone 7a. The average last spring frost is May 9 and the first fall frost is October 1, giving you a growing season of approximately 145 days.

At an elevation of 4,048 feet, Washington County receives approximately 17.9 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Christmas Lima Beans during the growing season. With low rainfall, drip irrigation is essential for growing Christmas Lima Beans successfully. Mulch heavily to conserve soil moisture.

Washington County, ID (Zone 7a) Short season
145 days
Last Spring Frost May 9
145 growing days
First Fall Frost October 1
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Washington County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (13 days to spare)
Start indoors: Mar 13 Transplant: May 15 🍅 Harvest: Aug 7 – Sep 11
Recommended (50%) ✓ Fits season (12 days to spare)
Start indoors: Mar 21 Transplant: May 23 🍅 Harvest: Aug 15 – Sep 19
Safe Start (90%) ✓ Fits season (3 days to spare)
Start indoors: Apr 19 Transplant: Jun 21 🍅 Harvest: Sep 13 – Oct 18

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 Washington County

How your county's soil matches Christmas Lima Beans's growing requirements.

Soil pH

Your soil pH (6.2–7.8) overlaps with Christmas Lima Beans's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Washington County is excellent for Christmas Lima Beans — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Christmas Lima Beans.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Christmas Lima Beans.

How to Plant Christmas Lima Beans

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Christmas Lima Beans

2
successive plantings in your 145-day season

Sow every 9.1 weeks. Last sowing by Jun 23 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,210 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Christmas Lima Beans

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

Month Christmas Lima Beans Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 1.7" 0" ❄️ Dormant
May 4.3" 2" 2.3" 🚿 Regular watering
Jun 4.3" 1.2" 3.1" 🚿 Regular watering
Jul 4.3" 1.6" 2.7" 🚿 Regular watering
Aug 4.3" 1.7" 2.6" 🚿 Regular watering
Sep 4.3" 1.5" 2.8" 🚿 Regular watering
Oct 4.3" 1.5" 2.8" 🚿 Regular watering
Nov 1.4" 0" ❄️ Dormant
Dec 1" 0" ❄️ Dormant

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

Christmas Lima Beans 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.

Christmas Lima Beans needs ~1,238 GDD — county provides 1,993 GDD Excellent fit

Christmas Lima Beans Planting Timeline — Washington County, ID

Christmas Lima Beans Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors May 23 May 23 – Jun 6
Direct Sow May 16 May 16 – Jun 6
Harvest August 15 Aug 15 – Sep 19

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

80–100 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

145 days in Washington County

Growing Tips for Christmas Lima Beans in Washington County

Direct sow Christmas Lima Beans outdoors after May 09 in Washington County when soil has warmed and frost danger has passed.

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

Washington County receives only 18" of rain annually. Christmas Lima Beans needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after soil is warm. Provide tall trellising for vigorous vines. Harvest for fresh shelling when pods are plump or allow to dry on the vine for storage.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Christmas Lima Beans in Washington County, ID?

Washington County is in Zone 7a with an average last frost of May 9. Plan your Christmas Lima Beans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, ID?

Washington County, Idaho is in USDA Hardiness Zone 7a. The average last spring frost is May 9 and first fall frost is October 1.

🌱

Your Washington County Garden Planner — Free

A 24-page printable planner built for Washington 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 Washington County, ID. 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.