When to plant Vinca (Annual) in Delta County, CO
In Delta County, Vinca (Annual) is a spring-only crop. Plant May 8–May 22 once soil hits 50°F.
When to Plant Vinca (Annual) in Delta County, CO
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.
Delta County, Colorado is in USDA Zone 6b. The average last spring frost is May 1 and the first fall frost is October 8, giving you a growing season of approximately 160 days.
At an elevation of 4,470 feet, Delta County receives approximately 13.4 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Vinca (Annual) during the growing season. With low rainfall, drip irrigation is essential for growing Vinca (Annual) successfully. Mulch heavily to conserve soil moisture.
Delta County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Vinca (Annual) Planting Timeline — Delta County, CO
Vinca (Annual) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Bloom | July 17 | Jul 17 – Oct 30 |
Plant 0.1" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
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 6b
📆 Growing Season
160 days in Delta County
Growing Tips for Delta 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 Delta County, CO?
Delta County is in Zone 6b with an average last frost of May 1. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Delta County, CO?
Delta County, Colorado is in USDA Hardiness Zone 6b. The average last spring frost is May 1 and first fall frost is October 8.
When should I plant Vinca (Annual) in Delta County, CO?
In Delta County, CO, plant Vinca (Annual) after the last frost (around May 1) and before the first frost (around October 8). Best results when soil holds above 50°F.
What growing zone is Delta County, CO for Vinca (Annual)?
Delta County sits in USDA Zone 6b. Vinca (Annual) grows reliably in zones 3a through 11b, so it's a good fit here.
Can Vinca (Annual) grow in Delta County's climate?
Yes — Vinca (Annual) grows well in Delta County's temperate climate. Delta County averages a 160-day frost-free season, with last frost around May 1 and first frost around October 8.
Your Delta County Garden Planner — Free
A 22-page printable planner built for Delta County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.