When to Plant Onion in Plaquemines Parish, LA
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.
Plaquemines Parish, Louisiana is in USDA Zone 9b. The average last spring frost is February 6 and the first fall frost is December 7, giving you a growing season of approximately 304 days.
At an elevation of 386 feet, Plaquemines Parish receives approximately 50.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Onion may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Onion will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Onion root diseases.
Plaquemines Parish Soil Profile
Soil Type
Sandy Loam
Soil pH
4.8-6
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.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Onion Planting Timeline — Plaquemines Parish, LA
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 9 | Jan 9 – Jan 23 |
| Transplant Outdoors | February 6 | Feb 6 – Feb 20 |
| Direct Sow | January 16 | Jan 16 – Feb 6 |
| Fall Sowing | October 12 | Oct 12 – Oct 26 |
| Harvest | May 8 | May 8 – Jun 26 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Direct Sow |
| February | Transplant Outdoors Direct Sow |
| March | — |
| April | — |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–120 days
Soil pH
6 – 7
USDA Zone
Zone 9b
Growing Season
304 days
Growing Tips for Plaquemines Parish
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
Level Up Your Garden
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Plaquemines Parish, LA?
Plaquemines Parish is in Zone 9b with an average last frost of February 6. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Plaquemines Parish, LA?
Plaquemines Parish, Louisiana is in USDA Hardiness Zone 9b. The average last spring frost is February 6 and first fall frost is December 7.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Plaquemines Parish gardeners in Zone 9b organize planting dates, track what's growing, and never miss a planting window.
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