Blog

When to Plant Daikon in Williamson County, TX

Daikon is a large, mild Japanese radish that can grow over a foot long. It is excellent for pickling, stir-fries, and as a soil-breaking cover crop.

Williamson County, Texas is in USDA Zone 8b. The average last spring frost is March 5 and the first fall frost is November 22, giving you a growing season of approximately 262 days.

At an elevation of 1,023 feet, Williamson County receives approximately 53.3 inches of rainfall annually with predominantly clay soil. Summer highs average 94ยฐF, providing good warmth for Daikon during the growing season. Clay soil retains moisture well for Daikon, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Daikon root diseases.

Williamson County, TX (Zone 8b) Long season
262 days
Last Spring Frost March 5
262 growing days
First Fall Frost November 22

Williamson County Soil Profile

Soil Type

Clay

Soil pH

7.1-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (180 days to spare)
Transplant: Feb 21 🍅 Harvest: Apr 18 – May 16
Recommended (50%) ✓ Fits season (178 days to spare)
Transplant: Mar 5 🍅 Harvest: Apr 30 – May 28
Safe Start (90%) ✓ Fits season (166 days to spare)
Transplant: Apr 6 🍅 Harvest: Jun 1 – Jun 29

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 Williamson County

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

Soil pH

Your soil pH (7.1โ€“7.8) is more alkaline than Daikon prefers (5.8โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Heavy clay soil (46% clay) in Williamson County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Drainage

Drainage is adequate for Daikon.

Organic Matter

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

How to Plant Daikon

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Daikon

6
successive plantings in your 262-day season

Sow every 5.7 weeks. Last sowing by Sep 13 to harvest before frost.

For a dedicated fall crop, sow by Sep 13.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Daikon

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

Month Daikon Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 2" 0" โ„๏ธ Dormant
Mar 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Apr 4.3" 6.5" 0" โœ… Rainfall sufficient
May 4.3" 7.7" 0" โœ… Rainfall sufficient
Jun 4.3" 7.6" 0" โœ… Rainfall sufficient
Jul 4.3" 6.6" 0" โœ… Rainfall sufficient
Aug 4.3" 6.1" 0" โœ… Rainfall sufficient
Sep 4.3" 5.4" 0" โœ… Rainfall sufficient
Oct 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Nov 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Dec โ€” 1.3" 0" โ„๏ธ Dormant

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

Daikon 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.

Daikon needs ~1,230 GDD — county provides 5,371 GDD Excellent fit

Daikon Planting Timeline โ€” Williamson County, TX

Daikon Planting Calendar

Activity When Date Range
Direct Sow February 19 Feb 19 โ€“ Mar 12
Harvest April 16 Apr 16 โ€“ May 14
Fall Sowing September 13 Sep 13 โ€“ Sep 27

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 5.8โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

262 days in Williamson County

Growing Tips for Daikon in Williamson County

Direct sow Daikon outdoors after March 05 in Williamson County when soil has warmed and frost danger has passed.

With Williamson County's clay soil (46% clay), work in 3-4 inches of compost before planting Daikon. Avoid tilling when soil is wet to prevent compaction.

Common pests for Daikon 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 late summer for fall harvest. Loosen soil deeply before planting. Thin seedlings to 6 inches apart. Harvest before hard freeze as exposed shoulders may crack.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Daikon in Williamson County, TX?

Williamson County is in Zone 8b with an average last frost of March 5. Plan your Daikon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Williamson County, TX?

Williamson County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 5 and first fall frost is November 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Williamson County gardeners in Zone 8b 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 Williamson County, TX. Local conditions may vary. Last updated: April 2026.