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When to Plant Onion in Avery County, NC

Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.

Avery County, North Carolina is in USDA Zone 6a. The average last spring frost is April 12 and the first fall frost is October 23, giving you a growing season of approximately 194 days.

At an elevation of 914 feet, Avery County receives approximately 43.7 inches of rainfall annually with predominantly clay loam soil. Summer highs average 91ยฐF, providing good warmth for Onion during the growing season. Clay soil retains moisture well for Onion, but amend with compost to improve drainage and prevent root rot.

Avery County, NC (Zone 6a) Moderate season
194 days
Last Spring Frost April 12
194 growing days
First Fall Frost October 23

Avery County Soil Profile

Soil Type

Clay Loam

Soil pH

5.3-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (56 days to spare)
Start indoors: Mar 2 Transplant: Apr 6 🍅 Harvest: Jul 6 – Aug 24
Recommended (50%) ✓ Fits season (54 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: Jul 12 – Aug 30
Safe Start (90%) ✓ Fits season (50 days to spare)
Start indoors: Mar 25 Transplant: Apr 29 🍅 Harvest: Jul 29 – Sep 16

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
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 112 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Onion needs ~1,916 GDD — county provides 3,540 GDD Excellent fit

Onion Planting Timeline โ€” Avery County, NC

Onion Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 โ€“ Mar 22
Transplant Outdoors April 12 Apr 12 โ€“ Apr 26
Direct Sow March 29 Mar 29 โ€“ Apr 19
Fall Sowing August 14 Aug 14 โ€“ Aug 28
Harvest July 12 Jul 12 โ€“ Aug 30

Plant 1" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

90โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6a

Growing Season

194 days

Growing Tips for Avery County

Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.

Companion Planting

Good Companions

Avoid Planting Near

  • Peas
  • Green Beans
  • Asparagus

Level Up Your Garden

Frequently Asked Questions

When should I plant Onion in Avery County, NC?

Avery County is in Zone 6a with an average last frost of April 12. Plan your Onion planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Avery County, NC?

Avery County, North Carolina is in USDA Hardiness Zone 6a. The average last spring frost is April 12 and first fall frost is October 23.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Avery County gardeners in Zone 6a 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 Avery County, NC. Local conditions may vary. Last updated: April 2026.