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When to Plant Mizuna in Willacy County, TX

Mizuna is a mild-flavored Japanese mustard green with feathery, deeply serrated leaves. It is fast-growing and makes an excellent addition to salads and stir-fries.

Willacy County, Texas is in USDA Zone 9b. The average last spring frost is February 4 and the first fall frost is December 22, giving you a growing season of approximately 321 days.

At an elevation of 1,085 feet, Willacy County receives approximately 65.9 inches of rainfall annually with predominantly loam soil. Summer highs average 102ยฐF, so Mizuna may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Mizuna root diseases.

Willacy County, TX (Zone 9b) Year-round
321 days
Last Spring Frost February 4
321 growing days
First Fall Frost December 22

Willacy County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (270 days to spare)
Start indoors: Dec 20 Transplant: Jan 17 🍅 Harvest: Feb 21 – Mar 21
Recommended (50%) ✓ Fits season (258 days to spare)
Start indoors: Jan 7 Transplant: Feb 4 🍅 Harvest: Mar 11 – Apr 8
Safe Start (90%) ✓ Fits season (235 days to spare)
Start indoors: Feb 4 Transplant: Mar 4 🍅 Harvest: Apr 8 – May 6

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 Willacy County

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

Soil pH

Your soil pH (6.5โ€“7.3) is within Mizuna's preferred range (6.0โ€“7.5).

Soil Texture

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

Drainage

Drainage is adequate for Mizuna.

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Mizuna.

How to Plant Mizuna

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

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

Succession Planting Mizuna

13
successive plantings in your 321-day season

Sow every 3.4 weeks. Last sowing by Nov 07 to harvest before frost.

For a dedicated fall crop, sow by Oct 27.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,515 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Mizuna

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

Month Mizuna Needs Rainfall You Supplement Action
Jan โ€” 1.7" 0" โ„๏ธ Dormant
Feb 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Mar 4.3" 4.4" 0" โœ… Rainfall sufficient
Apr 4.3" 6.4" 0" โœ… Rainfall sufficient
May 4.3" 9.5" 0" โœ… Rainfall sufficient
Jun 4.3" 9.7" 0" โœ… Rainfall sufficient
Jul 4.3" 9" 0" โœ… Rainfall sufficient
Aug 4.3" 8.5" 0" โœ… Rainfall sufficient
Sep 4.3" 6.3" 0" โœ… Rainfall sufficient
Oct 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Nov 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Dec 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering

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

Mizuna 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.

Mizuna needs ~994 GDD — county provides 8,533 GDD Excellent fit

Mizuna Planting Timeline โ€” Willacy County, TX

Mizuna Planting Calendar

Activity When Date Range
Start Indoors January 7 Jan 7 โ€“ Jan 21
Transplant Outdoors February 4 Feb 4 โ€“ Feb 18
Direct Sow January 14 Jan 14 โ€“ Feb 4
Harvest March 11 Mar 11 โ€“ Apr 8
Fall Sowing October 27 Oct 27 โ€“ Nov 10

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

30โ€“45 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 9b

๐Ÿ“† Growing Season

321 days in Willacy County

Growing Tips for Mizuna in Willacy County

Direct sow Mizuna outdoors after February 04 in Willacy County when soil has warmed and frost danger has passed.

With summer highs reaching 102ยฐF in Willacy County, provide afternoon shade for Mizuna and water deeply in the morning.

Your generous 322.0-day season in Willacy County allows multiple plantings of Mizuna. Sow every 15.0 days for continuous harvest.

Common pests for Mizuna in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in spring or fall. Harvest outer leaves as needed for a cut-and-come-again approach. Mizuna is one of the most cold-tolerant Asian greens.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mizuna in Willacy County, TX?

Willacy County is in Zone 9b with an average last frost of February 4. Plan your Mizuna planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Willacy County, TX?

Willacy County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 4 and first fall frost is December 22.

๐ŸŒฑ

Plan Your Garden with Confidence

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

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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 Willacy County, TX. Local conditions may vary. Last updated: April 2026.