When to Plant Scallions in St. Charles Parish, LA
Top priorities for St. Charles Parish, Louisiana gardeners in May
Welcome to May in Zone 9b. These are the moves that will have the biggest impact on your growing season.
-
Start harvesting scallions
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Scallions (green onions) are mild-flavored alliums harvested for their slender green tops and white bases. They are quick-growing and perfect for succession planting.
St. Charles Parish, Louisiana is in USDA Zone 9b. The average last spring frost is February 20 and the first fall frost is December 1, giving you a growing season of approximately 284 days.
At an elevation of 154 feet, St. Charles Parish receives approximately 54.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 103°F, so Scallions may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Scallions will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Scallions root diseases.
St. Charles Parish Soil Profile
Soil Type
Sandy Loam
Soil pH
4.9-6.3
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 St. Charles Parish
How your county's soil matches Scallions's growing requirements.
Soil pH
Your soil pH (4.9–6.3) is more acidic than Scallions prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in St. Charles Parish warms quickly in spring but drains fast. Scallions will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Scallions.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Scallions.
How to Plant Scallions
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Scallions
Sow every 5.7 weeks. Last sowing by Sep 22 to harvest before frost.
For a dedicated fall crop, sow by Oct 06.
Plant Water Budget
Monthly Watering Guide for Scallions
Scallions needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Scallions Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.3" | 0" | ❄️ Dormant |
| Feb | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Mar | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| May | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3" | 1.3" | 💧 Light watering |
| Nov | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Dec | 4.3" | 4" | 0.3" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in St. Charles Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Scallions 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.
Scallions Planting Timeline — St. Charles Parish, LA
Scallions Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 23 | Jan 23 – Feb 6 |
| Transplant Outdoors | February 20 | Feb 20 – Mar 6 |
| Direct Sow | January 30 | Jan 30 – Feb 20 |
| Harvest | April 17 | Apr 17 – May 15 |
| Fall Sowing | October 6 | Oct 6 – Oct 20 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Direct Sow |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Transplant Outdoors |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9b
📆 Growing Season
284 days in St. Charles Parish
Growing Tips for Scallions in St. Charles Parish
Direct sow Scallions outdoors after February 20 in St. Charles Parish when soil has warmed and frost danger has passed.
Sandy soil in St. Charles Parish dries quickly — mulch Scallions with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
With summer highs reaching 103°F in St. Charles Parish, provide afternoon shade for Scallions and water deeply in the morning.
Common pests for Scallions in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow every 3 weeks for continuous harvest. Thin to 1 inch apart or grow in clusters. Harvest when pencil-thick by pulling or cutting at soil level.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Scallions in Other Locations
Frequently Asked Questions
When should I plant Scallions in St. Charles Parish, LA?
St. Charles Parish is in Zone 9b with an average last frost of February 20. Plan your Scallions planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Charles Parish, LA?
St. Charles Parish, Louisiana is in USDA Hardiness Zone 9b. The average last spring frost is February 20 and first fall frost is December 1.
Your St. Charles Parish Garden Planner — Free
A 24-page printable planner built for St. Charles Parish (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.