When to Plant Radish in Polk County, FL
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.
Polk County, Florida is in USDA Zone 9b. The average last spring frost is January 25 and the first fall frost is December 19, giving you a growing season of approximately 328 days.
At an elevation of 236 feet, Polk County receives approximately 58.3 inches of rainfall annually with predominantly sand soil. Summer highs average 96°F, so Radish may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Radish will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radish root diseases.
Polk County Soil Profile
Soil Type
Sand
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 Polk County
How your county's soil matches Radish's growing requirements.
Soil pH
Your soil pH (4.9–6.3) is more acidic than Radish prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Polk County warms quickly in spring but drains fast. Radish will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Radish.
Organic Matter
Organic matter is low (1.6%). Add 2-3 inches of compost before planting Radish.
How to Plant Radish
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Radish
Sow every 2.4 weeks. Last sowing by Nov 14 to harvest before frost.
For a dedicated fall crop, sow by Oct 24.
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 | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Feb | 2.2" | 3.1" | 0" | ✅ Rainfall sufficient |
| Mar | 2.2" | 3.5" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 4.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 9.1" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 7.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 6.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.8" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Dec | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
Water needs are for active growing months only (Jan–Dec in Polk County). 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 — Polk County, FL
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | January 4 | Jan 4 – Jan 25 |
| Harvest | February 1 | Feb 1 – Feb 22 |
| Fall Sowing | October 24 | Oct 24 – Nov 7 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Direct Sow |
| February | Harvest |
| March | — |
| April | — |
| May | — |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | Fall Sowing |
| 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: too_acidic
🗺️ USDA Zone
Zone 9b
📆 Growing Season
328 days in Polk County
Growing Tips for Radish in Polk County
Direct sow Radish outdoors after January 25 in Polk County when soil has warmed and frost danger has passed.
Sandy soil in Polk County dries quickly — mulch Radish with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Summer highs in Polk County reach 96°F — grow Radish as a spring or fall crop. Use shade cloth if planting in summer.
Your generous 329.0-day season in Polk County 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.
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
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Check more plant combinations with our Companion Planting Checker →
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Polk County, FL?
Polk County is in Zone 9b with an average last frost of January 25. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Polk County, FL?
Polk County, Florida is in USDA Hardiness Zone 9b. The average last spring frost is January 25 and first fall frost is December 19.
Plan Your Garden with Confidence
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