When to Plant Vinca (Annual) in Humboldt County, NV
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.
Humboldt County, Nevada is in USDA Zone 6b. The average last spring frost is May 30 and the first fall frost is September 15, giving you a growing season of approximately 108 days.
At an elevation of 5,527 feet, Humboldt County receives approximately 8.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°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. With low rainfall, drip irrigation is essential for growing Vinca (Annual) successfully. Mulch heavily to conserve soil moisture.
Humboldt County Soil Profile
Soil Type
Sandy Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Vinca (Annual) Planting Timeline — Humboldt County, NV
Vinca (Annual) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 21 | Mar 21 – Apr 4 |
| Transplant Outdoors | June 6 | Jun 6 – Jun 20 |
| Bloom | August 15 | Aug 15 – Nov 28 |
Plant 0.1" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors |
| July | — |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| 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
108 days in Humboldt County
Growing Tips for Humboldt 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 Humboldt County, NV?
Humboldt County is in Zone 6b with an average last frost of May 30. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Humboldt County, NV?
Humboldt County, Nevada is in USDA Hardiness Zone 6b. The average last spring frost is May 30 and first fall frost is September 15.
Your Humboldt County Garden Planner — Free
A 22-page printable planner built for Humboldt 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.