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When to Plant Corn in Yolo County, CA

Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

Yolo County, California is in USDA Zone 9a. The average last spring frost is February 9 and the first fall frost is December 3, giving you a growing season of approximately 297 days.

At an elevation of 163 feet, Yolo County receives approximately 27.7 inches of rainfall annually with predominantly loam soil. Summer highs average 95ยฐF, so Corn may need afternoon shade and extra watering during peak heat.

Yolo County, CA (Zone 9a) Year-round
297 days
Last Spring Frost February 9
297 growing days
First Fall Frost December 3

Yolo County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (186 days to spare)
Transplant: Jan 25 🍅 Harvest: Mar 29 – May 24
Recommended (50%) ✓ Fits season (178 days to spare)
Transplant: Feb 9 🍅 Harvest: Apr 13 – Jun 8
Safe Start (90%) ✓ Fits season (162 days to spare)
Transplant: Mar 13 🍅 Harvest: May 15 – Jul 10

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
0.4″/week
You supply
0.7″/week
Watering frequency 2-3 times/week
Season total 1,940 gal / 100 sq ft
Drought risk

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

Corn needs ~1,700 GDD — county provides 6,332 GDD Excellent fit

Corn Planting Timeline โ€” Yolo County, CA

Corn Planting Calendar

Activity When Date Range
Direct Sow February 16 Feb 16 โ€“ Mar 9
Harvest April 20 Apr 20 โ€“ Jun 15

Plant 1" deep ยท 12" apart ยท Rows 36" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“100 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 9a

Growing Season

297 days

Growing Tips for Yolo County

Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Level Up Your Garden

Frequently Asked Questions

When should I plant Corn in Yolo County, CA?

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

What planting zone is Yolo County, CA?

Yolo County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 9 and first fall frost is December 3.

๐ŸŒฑ

Plan Your Garden with Confidence

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