When to Plant Radicchio in Starr County, TX
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.
Starr County, Texas is in USDA Zone 9b. The average last spring frost is February 3 and the first fall frost is December 16, giving you a growing season of approximately 316 days.
At an elevation of 2,451 feet, Starr County receives approximately 55.4 inches of rainfall annually with predominantly loam soil. Summer highs average 98°F, so Radicchio may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radicchio root diseases.
Starr County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.5
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 Starr County
How your county's soil matches Radicchio's growing requirements.
Soil pH
Your soil pH (6.8–7.5) is more alkaline than Radicchio prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Starr County is excellent for Radicchio — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). 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 27 to harvest before frost.
For a dedicated fall crop, sow by Oct 21.
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 3" | 1.9" | 1.1" | 💧 Light watering |
| Mar | 3" | 3.4" | 0" | ✅ Rainfall sufficient |
| Apr | 3" | 6.6" | 0" | ✅ Rainfall sufficient |
| May | 3" | 8.8" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 7.6" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 7" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 6.4" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Oct | 3" | 4" | 0" | ✅ Rainfall sufficient |
| Nov | 3" | 1.6" | 1.4" | 💧 Light watering |
| Dec | 3" | 1.6" | 1.4" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Starr County). 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 — Starr County, TX
Radicchio Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 6 | Jan 6 – Jan 20 |
| Transplant Outdoors | February 3 | Feb 3 – Feb 17 |
| Direct Sow | January 13 | Jan 13 – Feb 3 |
| Harvest | April 7 | Apr 7 – May 12 |
| Fall Sowing | October 21 | Oct 21 – Nov 4 |
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 | Fall Sowing |
| 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_alkaline
🗺️ USDA Zone
Zone 9b
📆 Growing Season
316 days in Starr County
Growing Tips for Radicchio in Starr County
Direct sow Radicchio outdoors after February 03 in Starr County when soil has warmed and frost danger has passed.
With summer highs reaching 98°F in Starr County, provide afternoon shade for Radicchio and water deeply in the morning.
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 Starr County, TX?
Starr County is in Zone 9b with an average last frost of February 3. Plan your Radicchio planting based on this frost date — see the calendar above for exact timing.
What planting zone is Starr County, TX?
Starr County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 3 and first fall frost is December 16.
Plan Your Garden with Confidence
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