When to Plant Onion in Jackson County, FL
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.
Jackson County, Florida is in USDA Zone 8b. The average last spring frost is March 6 and the first fall frost is November 19, giving you a growing season of approximately 258 days.
At an elevation of 223 feet, Jackson County receives approximately 48.5 inches of rainfall annually with predominantly sand soil. Summer highs average 92°F, providing good warmth for Onion during the growing season. Sandy soil warms quickly in spring — great for early planting — but Onion will need more frequent watering and organic matter to retain nutrients.
Jackson County Soil Profile
Soil Type
Sand
Soil pH
5.1-6
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.
Soil Compatibility in Jackson County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (5.1–6.0) is more acidic than Onion prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Jackson County warms quickly in spring but drains fast. Onion will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Onion.
Organic Matter
Organic matter is low (1.3%). Add 2-3 inches of compost before planting Onion.
How to Plant Onion
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 2.3" | 0" | ❄️ Dormant |
| Feb | — | 2.6" | 0" | ❄️ Dormant |
| Mar | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Apr | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| May | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Jun | 4.3" | 7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.2" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 7.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 6.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4" | 0.3" | 💧 Light watering |
| Nov | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Jackson 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 Planting Timeline — Jackson County, FL
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 30 | Jan 30 – Feb 13 |
| Transplant Outdoors | March 6 | Mar 6 – Mar 20 |
| Direct Sow | February 20 | Feb 20 – Mar 13 |
| Harvest | June 5 | Jun 5 – Jul 24 |
| Fall Sowing | September 10 | Sep 10 – Sep 24 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
258 days in Jackson County
Growing Tips for Onion in Jackson County
Direct sow Onion outdoors after March 06 in Jackson County when soil has warmed and frost danger has passed.
Sandy soil in Jackson County dries quickly — mulch Onion with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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
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Check more plant combinations with our Companion Planting Checker →
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Jackson County, FL?
Jackson County is in Zone 8b with an average last frost of March 6. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jackson County, FL?
Jackson County, Florida is in USDA Hardiness Zone 8b. The average last spring frost is March 6 and first fall frost is November 19.
Plan Your Garden with Confidence
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