Blog

When to Plant Mizuna in Starr 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.

Starr County, Texas is in USDA Zone 9b. The average last spring frost is February 3 and the first fall frost is December 16, giving you a growing season of approximately 316 days.

At an elevation of 2,451 feet, Starr County receives approximately 55.4 inches of rainfall annually with predominantly loam soil. Summer highs average 98ยฐF, 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.

Starr County, TX (Zone 9b) Year-round
316 days
Last Spring Frost February 3
316 growing days
First Fall Frost December 16

Starr County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (263 days to spare)
Start indoors: Dec 21 Transplant: Jan 18 🍅 Harvest: Feb 22 – Mar 22
Recommended (50%) ✓ Fits season (253 days to spare)
Start indoors: Jan 6 Transplant: Feb 3 🍅 Harvest: Mar 10 – Apr 7
Safe Start (90%) ✓ Fits season (234 days to spare)
Start indoors: Feb 3 Transplant: Mar 3 🍅 Harvest: Apr 7 – May 5

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 901 gal / 100 sq ft
Drought risk

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

Mizuna needs ~881 GDD — county provides 7,449 GDD Excellent fit

Mizuna Planting Timeline โ€” Starr County, TX

Mizuna Planting Calendar

Activity When Date Range
Start Indoors January 6 Jan 6 โ€“ Jan 20
Transplant Outdoors February 3 Feb 3 โ€“ Feb 17
Direct Sow January 13 Jan 13 โ€“ Feb 3
Fall Sowing October 21 Oct 21 โ€“ Nov 4
Harvest March 10 Mar 10 โ€“ Apr 7

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

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

30โ€“45 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 9b

Growing Season

316 days

Growing Tips for Starr County

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Mizuna in Starr County, TX?

Starr County is in Zone 9b with an average last frost of February 3. Plan your Mizuna planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Starr County, TX?

Starr County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 3 and first fall frost is December 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Starr County gardeners in Zone 9b 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 Starr County, TX. Local conditions may vary. Last updated: April 2026.