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When to Plant Radish in Clark County, NV

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.

Clark County, Nevada is in USDA Zone 9a. The average last spring frost is February 28 and the first fall frost is November 23, giving you a growing season of approximately 268 days.

At an elevation of 2,811 feet, Clark County receives approximately 9.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 111ยฐF, so Radish may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Radish will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Radish successfully. Mulch heavily to conserve soil moisture.

Clark County, NV (Zone 9a) Long season
268 days
Last Spring Frost February 28
268 growing days
First Fall Frost November 23

Clark County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (224 days to spare)
Transplant: Feb 11 🍅 Harvest: Mar 11 – Apr 1
Recommended (50%) ✓ Fits season (219 days to spare)
Transplant: Feb 28 🍅 Harvest: Mar 28 – Apr 18
Safe Start (90%) ✓ Fits season (205 days to spare)
Transplant: Apr 5 🍅 Harvest: May 3 – May 24

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 Clark County

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

Soil pH

Your soil pH (7.3โ€“8.4) is more alkaline than Radish prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Clark County warms quickly in spring but drains fast. Radish will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Radish.

Organic Matter

Organic matter is low (0.8%). Add 2-3 inches of compost before planting 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

15
successive plantings in your 268-day season

Sow every 2.4 weeks. Last sowing by Oct 19 to harvest before frost.

For a dedicated fall crop, sow by Sep 28.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.2″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,450 gal / 100 sq ft
Drought risk

Water stress score is 10/10 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€” 0.7" 0" โ„๏ธ Dormant
Feb 2.2" 0.6" 1.6" ๐Ÿšฟ Regular watering
Mar 2.2" 0.6" 1.6" ๐Ÿšฟ Regular watering
Apr 2.2" 0.3" 1.9" ๐Ÿšฟ Regular watering
May 2.2" 0.2" 2" ๐Ÿšฟ Regular watering
Jun 2.2" 0.3" 1.9" ๐Ÿšฟ Regular watering
Jul 2.2" 1.5" 0.7" ๐Ÿ’ง Light watering
Aug 2.2" 1.9" 0.3" ๐Ÿ’ง Light watering
Sep 2.2" 1.2" 1" ๐Ÿ’ง Light watering
Oct 2.2" 0.9" 1.3" ๐Ÿšฟ Regular watering
Nov 2.2" 0.5" 1.7" ๐Ÿšฟ Regular watering
Dec โ€” 0.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Febโ€“Nov in Clark 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 ~948 GDD — county provides 8,944 GDD Excellent fit

Radish Planting Timeline โ€” Clark County, NV

Radish Planting Calendar

Activity When Date Range
Direct Sow February 7 Feb 7 โ€“ Feb 28
Harvest March 7 Mar 7 โ€“ Mar 28
Fall Sowing September 28 Sep 28 โ€“ Oct 12

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

22โ€“35 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 9a

๐Ÿ“† Growing Season

268 days in Clark County

Growing Tips for Radish in Clark County

Direct sow Radish outdoors after February 28 in Clark County when soil has warmed and frost danger has passed.

Sandy soil in Clark County dries quickly โ€” mulch Radish with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Summer highs in Clark County reach 111ยฐF โ€” grow Radish as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 269.0-day season in Clark 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 Clark County, NV?

Clark County is in Zone 9a with an average last frost of February 28. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clark County, NV?

Clark County, Nevada is in USDA Hardiness Zone 9a. The average last spring frost is February 28 and first fall frost is November 23.

๐ŸŒฑ

Plan Your Garden with Confidence

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