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When to Plant Sorrel in Merced County, CA

Sorrel is a perennial herb with tangy, lemon-flavored arrow-shaped leaves. It is one of the first greens to emerge in spring and is used in soups and salads.

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 Sorrel during the growing season. With low rainfall, drip irrigation is essential for growing Sorrel 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 (191 days to spare)
Start indoors: Jan 9 Transplant: Jan 30 🍅 Harvest: Mar 13 – May 15
Recommended (50%) ✓ Fits season (179 days to spare)
Start indoors: Jan 27 Transplant: Feb 17 🍅 Harvest: Mar 31 – Jun 2
Safe Start (90%) ✓ Fits season (144 days to spare)
Start indoors: Mar 21 Transplant: Apr 11 🍅 Harvest: May 23 – Jul 25

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 Sorrel's growing requirements.

Soil pH

Your soil pH (6.8โ€“7.7) is more alkaline than Sorrel prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

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

How to Plant Sorrel

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Sorrel

8
successive plantings in your 277-day season

Sow every 4.6 weeks. Last sowing by Sep 29 to harvest before frost.

For a dedicated fall crop, sow by Oct 03.

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 Sorrel

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

Month Sorrel 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.

Sorrel 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.

Sorrel needs ~762 GDD — county provides 4,239 GDD Excellent fit

Sorrel Planting Timeline โ€” Merced County, CA

Sorrel Planting Calendar

Activity When Date Range
Start Indoors January 27 Jan 27 โ€“ Feb 10
Transplant Outdoors February 17 Feb 17 โ€“ Mar 3
Direct Sow February 3 Feb 3 โ€“ Feb 24
Harvest March 31 Mar 31 โ€“ Jun 2
Fall Sowing October 3 Oct 3 โ€“ Oct 17

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

277 days in Merced County

Growing Tips for Sorrel in Merced County

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

Your generous 278.0-day season in Merced County allows multiple plantings of Sorrel. Sow every 20.0 days for continuous harvest.

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

General growing tips

Direct sow in early spring or fall. Remove flower stalks promptly to encourage leaf production. Divide clumps every 3-4 years. Young leaves have the best flavor.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sorrel in Merced County, CA?

Merced County is in Zone 9a with an average last frost of February 24. Plan your Sorrel 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.