When to Plant Vinca (Annual) in Madison County, TX
Annual vinca (Catharanthus roseus), also called Madagascar periwinkle, is one of the most heat- and drought-tolerant bedding plants available. Glossy foliage stays attractive all season while cheerful pinwheel blooms continue without deadheading. A top performer in hot, humid Southern summers where impatiens and begonias struggle. Self-cleaning; requires little maintenance once established.
Madison County, Texas is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 20, giving you a growing season of approximately 260 days.
At an elevation of 122 feet, Madison County receives approximately 57.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91°F, providing good warmth for Vinca (Annual) during the growing season. Sandy soil warms quickly in spring — great for early planting — but Vinca (Annual) will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Vinca (Annual) root diseases.
Madison County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.5-6.5
Drainage
Well Drained
Monthly Watering Guide for Vinca (Annual)
Vinca (Annual) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Vinca (Annual) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Apr | 4.3" | 6.6" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.1" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 9.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 6.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Nov | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Madison County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Vinca (Annual) Planting Timeline — Madison County, TX
Vinca (Annual) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 25 | Dec 25 – Jan 8 |
| Transplant Outdoors | February 12 | Feb 12 – Feb 26 |
| Bloom | April 23 | Apr 23 – Oct 22 |
Plant 0.1" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors |
| March | — |
| April | Bloom |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | Start Indoors |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 9a
📆 Growing Season
260 days in Madison County
Growing Tips for Madison County
Start seeds indoors 10–12 weeks before last frost — germination requires warm soil (75–80°F) and darkness. Do not cover seeds deeply; they need just a light dusting. Direct sowing is rarely practiced due to slow seedling establishment. Transplant after soil warms and frost danger has passed. Excellent drought tolerance once established; avoid overwatering. Performs best in well-drained beds or containers in full sun.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Vinca (Annual) in Other Locations
Frequently Asked Questions
When should I plant Vinca (Annual) in Madison County, TX?
Madison County is in Zone 9a with an average last frost of March 5. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madison County, TX?
Madison County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 20.
Your Madison County Garden Planner — Free
A 22-page printable planner built for Madison County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.