Blog

When to Plant Onion in Macon County, AL

Macon County, Alabama Zone 8b May

May in the garden — Macon County, Alabama

Your garden in Macon County, Alabama is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost March 25
Avg. first frost November 6
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
Coming up in June — start thinking about
  • First harvests: onion

Instant PDF download. No spam, unsubscribe any time.

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.

Macon County, Alabama is in USDA Zone 8b. The average last spring frost is March 25 and the first fall frost is November 6, giving you a growing season of approximately 226 days.

At an elevation of 450 feet, Macon County receives approximately 60 inches of rainfall annually with predominantly clay loam soil. Summer highs average 96°F, so Onion may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Onion, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.

Macon County, AL (Zone 8b) Long season
226 days
Last Spring Frost March 25
226 growing days
First Fall Frost November 6

Macon County Soil Profile

Soil Type

Clay Loam

Soil pH

5.2-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (95 days to spare)
Start indoors: Feb 1 Transplant: Mar 8 🍅 Harvest: Jun 7 – Jul 26
Recommended (50%) ✓ Fits season (86 days to spare)
Start indoors: Feb 18 Transplant: Mar 25 🍅 Harvest: Jun 24 – Aug 12
Safe Start (90%) ✓ Fits season (85 days to spare)
Start indoors: Mar 13 Transplant: Apr 17 🍅 Harvest: Jul 17 – Sep 4

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 Macon County

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

Soil pH

Your soil pH (5.2–6.3) is more acidic than Onion prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The clay loam soil in Macon County is excellent for Onion — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Onion.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Onion.

How to Plant Onion

1"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Onion

Onion needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Onion Needs Rainfall You Supplement Action
Jan 4.3" 0" ❄️ Dormant
Feb 4.9" 0" ❄️ Dormant
Mar 4.3" 5.8" 0" ✅ Rainfall sufficient
Apr 4.3" 5" 0" ✅ Rainfall sufficient
May 4.3" 5.4" 0" ✅ Rainfall sufficient
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 6.7" 0" ✅ Rainfall sufficient
Aug 4.3" 5.6" 0" ✅ Rainfall sufficient
Sep 4.3" 4.6" 0" ✅ Rainfall sufficient
Oct 4.3" 3.9" 0.4" 💧 Light watering
Nov 4.3" 4.7" 0" ✅ Rainfall sufficient
Dec 4.3" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Macon County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Onion 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" — every day above 50°F 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.

Onion needs ~2,310 GDD — county provides 4,972 GDD Excellent fit

Onion Planting Timeline — Macon County, AL

Onion Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors March 25 Mar 25 – Apr 8
Direct Sow March 11 Mar 11 – Apr 1
Harvest June 24 Jun 24 – Aug 12
Fall Sowing August 28 Aug 28 – Sep 11

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8b

📆 Growing Season

226 days in Macon County

Growing Tips for Onion in Macon County

Direct sow Onion outdoors after March 25 in Macon County when soil has warmed and frost danger has passed.

With Macon County's clay soil (31% clay), work in 3-4 inches of compost before planting Onion. Avoid tilling when soil is wet to prevent compaction.

With summer highs reaching 96°F in Macon County, provide afternoon shade for Onion and water deeply in the morning.

Common pests for Onion in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.

General growing tips

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Onion in Macon County, AL?

Macon County is in Zone 8b with an average last frost of March 25. Plan your Onion planting based on this frost date — see the calendar above for exact timing.

What planting zone is Macon County, AL?

Macon County, Alabama is in USDA Hardiness Zone 8b. The average last spring frost is March 25 and first fall frost is November 6.

🌱

Your Macon County Garden Planner — Free

A 24-page printable planner built for Macon County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Macon County, AL. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.