When to Plant Vinca (Annual) in Hardin 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.
Hardin County, Texas is in USDA Zone 9a. The average last spring frost is February 14 and the first fall frost is December 4, giving you a growing season of approximately 293 days.
At an elevation of 323 feet, Hardin County receives approximately 66.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 90°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.
Hardin County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.3-6.7
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Mar | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Apr | 4.3" | 7.7" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 10.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 11.2" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 9.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 7.2" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Nov | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Dec | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Hardin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Vinca (Annual) Planting Timeline — Hardin County, TX
Vinca (Annual) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 6 | Dec 6 – Dec 20 |
| Transplant Outdoors | January 24 | Jan 24 – Feb 7 |
| Bloom | April 4 | Apr 4 – Oct 3 |
Plant 0.1" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Transplant Outdoors |
| 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
293 days in Hardin County
Growing Tips for Hardin 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 Hardin County, TX?
Hardin County is in Zone 9a with an average last frost of February 14. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hardin County, TX?
Hardin County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 14 and first fall frost is December 4.
Your Hardin County Garden Planner — Free
A 22-page printable planner built for Hardin 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.