When to Plant Radish in Union Parish, LA
Top priorities for Union Parish, Louisiana gardeners in May
Here's what deserves your attention in Union Parish, Louisiana this month. Everything below is tailored to Zone 8b and timed around your local frost dates.
Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.
Union Parish, Louisiana is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 5, giving you a growing season of approximately 228 days.
At an elevation of 426 feet, Union Parish receives approximately 57.4 inches of rainfall annually with predominantly loam soil. Summer highs average 96°F, so Radish may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radish root diseases.
Union Parish Soil Profile
Soil Type
Loam
Soil pH
5.9-7
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 Union Parish
How your county's soil matches Radish's growing requirements.
Soil pH
Your soil pH (5.9–7.0) overlaps with Radish's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Union Parish is excellent for Radish — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Radish.
How to Plant Radish
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Radish
Sow every 2.4 weeks. Last sowing by Oct 01 to harvest before frost.
For a dedicated fall crop, sow by Aug 27.
Plant Water Budget
Monthly Watering Guide for Radish
Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Radish Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.6" | 0" | ❄️ Dormant |
| Feb | — | 4.7" | 0" | ❄️ Dormant |
| Mar | 2.2" | 4.7" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 5.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 6.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 5.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 5" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Union Parish). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Radish 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.
Radish Planting Timeline — Union Parish, LA
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 8 | Mar 8 – Mar 29 |
| Harvest | April 5 | Apr 5 – Apr 26 |
| Fall Sowing | August 27 | Aug 27 – Sep 10 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Harvest |
| May | — |
| June | — |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
22–35 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
228 days in Union Parish
Growing Tips for Radish in Union Parish
Direct sow Radish outdoors after March 22 in Union Parish when soil has warmed and frost danger has passed.
Summer highs in Union Parish reach 96°F — grow Radish as a spring or fall crop. Use shade cloth if planting in summer.
Your generous 228.0-day season in Union Parish allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.
Common pests for Radish in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
With 57" of annual rainfall in Union Parish, ensure good drainage for Radish — excess moisture can promote root rot and fungal diseases.
General growing tips
Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Union Parish, LA?
Union Parish is in Zone 8b with an average last frost of March 22. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union Parish, LA?
Union Parish, Louisiana is in USDA Hardiness Zone 8b. The average last spring frost is March 22 and first fall frost is November 5.
Your Union Parish Garden Planner — Free
A 24-page printable planner built for Union Parish (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.