When to Plant Radicchio in St. Mary Parish, LA
May to-do list for St. Mary Parish, Louisiana
May is a pivotal month for St. Mary Parish, Louisiana gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Collect radicchio at their peak
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
Radicchio is an Italian chicory with stunning red and white leaves and a pleasantly bitter flavor. It forms tight heads and is used in salads, grilled, or braised.
St. Mary Parish, Louisiana is in USDA Zone 9b. The average last spring frost is February 14 and the first fall frost is December 5, giving you a growing season of approximately 294 days.
At an elevation of 252 feet, St. Mary Parish receives approximately 48.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°F, so Radicchio may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Radicchio will need more frequent watering and organic matter to retain nutrients.
St. Mary Parish Soil Profile
Soil Type
Sandy Loam
Soil pH
4.8-6.4
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. Mary Parish
How your county's soil matches Radicchio's growing requirements.
Soil pH
Your soil pH (4.8–6.4) is more acidic than Radicchio prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in St. Mary Parish warms quickly in spring but drains fast. Radicchio will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Radicchio.
Organic Matter
Organic matter is moderate (2.0%). Annual compost additions will help Radicchio.
How to Plant Radicchio
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Radicchio
Sow every 6.9 weeks. Last sowing by Sep 16 to harvest before frost.
For a dedicated fall crop, sow by Oct 10.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Radicchio
Radicchio needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Radicchio Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.6" | 0" | ❄️ Dormant |
| Feb | 3" | 3.4" | 0" | ✅ Rainfall sufficient |
| Mar | 3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Apr | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| May | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.5" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 3.1" | 0" | ✅ Rainfall sufficient |
| Nov | 3" | 3.9" | 0" | ✅ Rainfall sufficient |
| Dec | 3" | 4.2" | 0" | ✅ Rainfall sufficient |
Water needs are for active growing months only (Feb–Dec in St. Mary Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Radicchio 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.
Radicchio Planting Timeline — St. Mary Parish, LA
Radicchio Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 17 | Jan 17 – Jan 31 |
| Transplant Outdoors | February 14 | Feb 14 – Feb 28 |
| Direct Sow | January 24 | Jan 24 – Feb 14 |
| Harvest | April 18 | Apr 18 – May 23 |
| Fall Sowing | October 10 | Oct 10 – Oct 24 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Direct Sow |
| February | Transplant Outdoors Direct Sow |
| March | — |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.7"/week · Natural rainfall sufficient
📅 Days to Maturity
60–80 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9b
📆 Growing Season
294 days in St. Mary Parish
Growing Tips for Radicchio in St. Mary Parish
Direct sow Radicchio outdoors after February 14 in St. Mary Parish when soil has warmed and frost danger has passed.
Sandy soil in St. Mary Parish dries quickly — mulch Radicchio with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Radicchio in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Start in late summer for fall harvest. The red color develops with cool nights and light frost. Harvest when heads are firm and compact.
Companion Planting
Good Companions
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Radicchio in Other Locations
Frequently Asked Questions
When should I plant Radicchio in St. Mary Parish, LA?
St. Mary Parish is in Zone 9b with an average last frost of February 14. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.
What planting zone is St. Mary Parish, LA?
St. Mary Parish, Louisiana is in USDA Hardiness Zone 9b. The average last spring frost is February 14 and first fall frost is December 5.
Your St. Mary Parish Garden Planner — Free
A 24-page printable planner built for St. Mary 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.