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When to Plant Radish in Kings County, CA

Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

Kings County, California is in USDA Zone 9a. The average last spring frost is February 14 and the first fall frost is December 2, giving you a growing season of approximately 291 days.

At an elevation of 2,065 feet, Kings County receives approximately 18.8 inches of rainfall annually with predominantly loam soil. Summer highs average 102ยฐF, so Radish may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Radish successfully. Mulch heavily to conserve soil moisture.

Kings County, CA (Zone 9a) Year-round
291 days
Last Spring Frost February 14
291 growing days
First Fall Frost December 2

Kings County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (248 days to spare)
Transplant: Jan 31 🍅 Harvest: Feb 28 – Mar 21
Recommended (50%) ✓ Fits season (242 days to spare)
Transplant: Feb 14 🍅 Harvest: Mar 14 – Apr 4
Safe Start (90%) ✓ Fits season (240 days to spare)
Transplant: Mar 8 🍅 Harvest: Apr 5 – Apr 26

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 Kings County

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

Soil pH

Your soil pH (6.5โ€“7.4) overlaps with Radish's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Radish.

How to Plant Radish

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

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

Succession Planting Radish

16
successive plantings in your 291-day season

Sow every 2.4 weeks. Last sowing by Oct 28 to harvest before frost.

For a dedicated fall crop, sow by Oct 07.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.3″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 716 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Radish

Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Radish Needs Rainfall You Supplement Action
Jan โ€” 3.6" 0" โ„๏ธ Dormant
Feb 2.2" 4" 0" โœ… Rainfall sufficient
Mar 2.2" 3.2" 0" โœ… Rainfall sufficient
Apr 2.2" 1.4" 0.8" ๐Ÿ’ง Light watering
May 2.2" 0.5" 1.7" ๐Ÿšฟ Regular watering
Jun 2.2" 0.1" 2.1" ๐Ÿšฟ Regular watering
Jul 2.2" 0" 2.2" ๐Ÿšฟ Regular watering
Aug 2.2" 0" 2.2" ๐Ÿšฟ Regular watering
Sep 2.2" 0.2" 2" ๐Ÿšฟ Regular watering
Oct 2.2" 0.7" 1.5" ๐Ÿšฟ Regular watering
Nov 2.2" 1.9" 0.3" ๐Ÿ’ง Light watering
Dec 2.2" 3.2" 0" โœ… Rainfall sufficient

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

Radish 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.

Radish needs ~755 GDD — county provides 7,738 GDD Excellent fit

Radish Planting Timeline โ€” Kings County, CA

Radish Planting Calendar

Activity When Date Range
Direct Sow January 24 Jan 24 โ€“ Feb 14
Harvest February 21 Feb 21 โ€“ Mar 14
Fall Sowing October 7 Oct 7 โ€“ Oct 21

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

22โ€“35 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

291 days in Kings County

Growing Tips for Radish in Kings County

Direct sow Radish outdoors after February 14 in Kings County when soil has warmed and frost danger has passed.

Summer highs in Kings County reach 102ยฐF โ€” grow Radish as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 292.0-day season in Kings County allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.

Common pests for Radish 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 every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radish in Kings County, CA?

Kings County is in Zone 9a with an average last frost of February 14. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Kings County, CA?

Kings County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 14 and first fall frost is December 2.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Kings 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 Kings County, CA. Local conditions may vary. Last updated: April 2026.