When to plant Vinca (Annual) in Lawrence County, KY
In Lawrence County, Vinca (Annual) is a single-season spring crop — there's no second fall window. Plant April 21–May 5 for an 70–90-day harvest, finishing well before the October 26 first frost.
When to Plant Vinca (Annual) in Lawrence County, KY
Lawrence County, Kentucky gardeners: here's your July plan
Each item below is timed to Lawrence County, Kentucky's frost dates and soil temperatures. Skip nothing, stress about nothing.
-
Collect vinca (annual) at their peak
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
To set up a strong August, finish these tasks
- First harvests: vinca (annual)
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.
Lawrence County, Kentucky is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 26, giving you a growing season of approximately 195 days.
At an elevation of 2,351 feet, Lawrence County receives approximately 40.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Vinca (Annual) during the growing season.
Lawrence County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.8
Drainage
Well Drained
Vinca (Annual) 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 Lawrence County
How your county's soil matches Vinca (Annual)'s growing requirements.
Soil pH
Your soil pH (5.5–6.8) overlaps with Vinca (Annual)'s range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Lawrence County is excellent for Vinca (Annual) — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Vinca (Annual) prefers dry conditions but your soil drains poorly. Use raised beds or mounded rows to prevent root rot.
Organic Matter
Organic matter is moderate (3.2%). Annual compost additions will help Vinca (Annual).
How to Plant Vinca (Annual)
Succession Planting Vinca (Annual)
Sow every 8 weeks. Last sowing by Jul 28 to harvest before frost.
Vinca (Annual) Water Budget
Monthly Watering Guide for Vinca (Annual)
Vinca (Annual) needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Vinca (Annual) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.5" | 0" | ❄️ Dormant |
| Feb | — | 3.3" | 0" | ❄️ Dormant |
| Mar | — | 3.8" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3" | 0" | ❄️ Dormant |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Lawrence County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Vinca (Annual) 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.
Vinca (Annual) Planting Timeline — Lawrence County, KY
Vinca (Annual) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 3 | Feb 3 – Feb 17 |
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Bloom | June 30 | Jun 30 – Oct 13 |
Plant 0.1" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
195 days in Lawrence County
Growing Tips for Vinca (Annual) in Lawrence County
Direct sow Vinca (Annual) outdoors after April 14 in Lawrence County when soil has warmed and frost danger has passed.
General growing tips
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 Lawrence County, KY?
Lawrence County is in Zone 6b with an average last frost of April 14. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lawrence County, KY?
Lawrence County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 26.
When should I plant Vinca (Annual) in Lawrence County, KY?
In Lawrence County, KY, plant Vinca (Annual) after the last frost (around April 14) and before the first frost (around October 26). Best results when soil holds above 50°F.
What growing zone is Lawrence County, KY for Vinca (Annual)?
Lawrence 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 Lawrence County's climate?
Yes — Vinca (Annual) grows well in Lawrence County's temperate climate. Lawrence County averages a 195-day frost-free season, with last frost around April 14 and first frost around October 26.
Your Lawrence County Garden Planner — Free
A 22-page printable planner built for Lawrence 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.