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When to Plant Kidney Beans in Merced County, CA

Kidney beans are a popular dry bean variety named for their shape, available in red and white types. They are the classic bean for chili and red beans and rice.

Merced County, California is in USDA Zone 9a. The average last spring frost is February 24 and the first fall frost is November 28, giving you a growing season of approximately 277 days.

At an elevation of 269 feet, Merced County receives approximately 18.8 inches of rainfall annually with predominantly loam soil. Summer highs average 87ยฐF, providing good warmth for Kidney Beans during the growing season. With low rainfall, drip irrigation is essential for growing Kidney Beans successfully. Mulch heavily to conserve soil moisture.

Merced County, CA (Zone 9a) Year-round
277 days
Last Spring Frost February 24
277 growing days
First Fall Frost November 28

Merced County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (163 days to spare)
Transplant: Feb 6 🍅 Harvest: May 8 – Jun 12
Recommended (50%) ✓ Fits season (151 days to spare)
Transplant: Feb 24 🍅 Harvest: May 26 – Jun 30
Safe Start (90%) ✓ Fits season (116 days to spare)
Transplant: Apr 18 🍅 Harvest: Jul 18 – Aug 22

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 Merced County

How your county's soil matches Kidney Beans's growing requirements.

Soil pH

Your soil pH (6.8โ€“7.7) overlaps with Kidney Beans's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Merced County is excellent for Kidney Beans โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Kidney Beans.

How to Plant Kidney Beans

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.3″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 2,126 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Kidney Beans

Kidney 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 Kidney Beans Needs Rainfall You Supplement Action
Jan โ€” 4.4" 0" โ„๏ธ Dormant
Feb 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Mar 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Apr 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
May 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Jun 4.3" 0.1" 4.2" ๐Ÿšฟ Regular watering
Jul 4.3" 0" 4.3" ๐Ÿšฟ Regular watering
Aug 4.3" 0" 4.3" ๐Ÿšฟ Regular watering
Sep 4.3" 0.2" 4.1" ๐Ÿšฟ Regular watering
Oct 4.3" 0.7" 3.6" ๐Ÿšฟ Regular watering
Nov 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Dec โ€” 3.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Febโ€“Nov in Merced County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Kidney 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" โ€” every day above 50ยฐF 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.

Kidney Beans needs ~1,487 GDD — county provides 4,239 GDD Excellent fit

Kidney Beans Planting Timeline โ€” Merced County, CA

Kidney Beans Planting Calendar

Activity When Date Range
Direct Sow March 3 Mar 3 โ€“ Mar 24
Harvest June 2 Jun 2 โ€“ Jul 7

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April โ€”
May โ€”
June Harvest
July Harvest
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

85โ€“110 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

277 days in Merced County

Growing Tips for Kidney Beans in Merced County

Direct sow Kidney Beans outdoors after February 24 in Merced County when soil has warmed and frost danger has passed.

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

Merced County receives only 19" of rain annually. Kidney Beans needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after frost. Allow pods to dry completely on the plant. Kidney beans must be thoroughly cooked as raw or undercooked beans contain harmful lectins.

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 Kidney Beans in Merced County, CA?

Merced County is in Zone 9a with an average last frost of February 24. Plan your Kidney Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Merced County, CA?

Merced County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 24 and first fall frost is November 28.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Merced County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Merced County, CA. Local conditions may vary. Last updated: April 2026.