When to Plant Radish in Kern 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.
Kern County, California is in USDA Zone 9a. The average last spring frost is February 28 and the first fall frost is November 29, giving you a growing season of approximately 274 days.
At an elevation of 389 feet, Kern County receives approximately 16.9 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, 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.
Kern County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.7
Drainage
Well Drained
Plant Planting Risk Windows
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
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Radish Planting Timeline — Kern County, CA
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 7 | Feb 7 – Feb 28 |
| Fall Sowing | October 4 | Oct 4 – Oct 18 |
| Harvest | March 7 | Mar 7 – Mar 28 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | Harvest |
| April | — |
| May | — |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
22–35 days
Soil pH
6 – 7
USDA Zone
Zone 9a
Growing Season
274 days
Growing Tips for Kern County
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
Level Up Your Garden
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Kern County, CA?
Kern County is in Zone 9a with an average last frost of February 28. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kern County, CA?
Kern County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 28 and first fall frost is November 29.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Kern County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
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