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When to Plant Vinca (Annual) in Tyler County, TX

Tyler County, Texas Zone 9a July

Tyler County, Texas gardeners: here's your July plan

Welcome to July in Zone 9a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 6
Avg. first frost November 19
Soil temp (4") 91°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Pick vinca (annual)

    If you can't use it all right away, check the food-preservation section of your planner.

August prep starts now
  • First harvests: vinca (annual)

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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.

Tyler County, Texas is in USDA Zone 9a. The average last spring frost is March 6 and the first fall frost is November 19, giving you a growing season of approximately 258 days.

At an elevation of 378 feet, Tyler County receives approximately 75.3 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°F, so Vinca (Annual) may need afternoon shade and extra watering during peak heat. 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.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant
Tyler County, TX (Zone 9a) Long season
258 days
Last Spring Frost March 6
258 growing days
First Fall Frost November 19

Tyler County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.4-6.3

Drainage

Well Drained

Vinca (Annual) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (31 days to spare)
Start indoors: Dec 16 Transplant: Feb 3 🌸 Bloom: Apr 14 – Oct 13
Recommended (50%) ✓ Fits season (27 days to spare)
Start indoors: Dec 26 Transplant: Feb 13 🌸 Bloom: Apr 24 – Oct 23
Safe Start (90%) ✓ Fits season (18 days to spare)
Start indoors: Jan 19 Transplant: Mar 9 🌸 Bloom: May 18 – Nov 16

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 Tyler County

How your county's soil matches Vinca (Annual)'s growing requirements.

Soil pH

Your soil pH (5.4–6.3) is more acidic than Vinca (Annual) prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Tyler County warms quickly in spring but drains fast. Vinca (Annual) will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Vinca (Annual).

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Vinca (Annual).

How to Plant Vinca (Annual)

0.1"
Planting Depth
10"
Between Plants
12"
Between Rows

Succession Planting Vinca (Annual)

4
successive plantings in your 258-day season

Sow every 8 weeks. Last sowing by Aug 21 to harvest before frost.

Vinca (Annual) Water Budget

Plant needs
0.5″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 1.8" 0" ❄️ Dormant
Feb 2.7" 0" ❄️ Dormant
Mar 2.2" 4.7" 0" ✅ Rainfall sufficient
Apr 2.2" 7.1" 0" ✅ Rainfall sufficient
May 2.2" 11.7" 0" ✅ Rainfall sufficient
Jun 2.2" 13.2" 0" ✅ Rainfall sufficient
Jul 2.2" 9.7" 0" ✅ Rainfall sufficient
Aug 2.2" 8.6" 0" ✅ Rainfall sufficient
Sep 2.2" 7.2" 0" ✅ Rainfall sufficient
Oct 2.2" 4.3" 0" ✅ Rainfall sufficient
Nov 2.2" 2.4" 0" ✅ Rainfall sufficient
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Tyler 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) needs ~1,700 GDD — county provides 5,482 GDD Excellent fit

Vinca (Annual) Planting Timeline — Tyler County, TX

Vinca (Annual) Planting Calendar

Activity When Date Range
Start Indoors December 26 Dec 26 – Jan 9
Transplant Outdoors February 13 Feb 13 – Feb 27
Bloom April 24 Apr 24 – Oct 23

Plant 0.1" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
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

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

258 days in Tyler County

Growing Tips for Vinca (Annual) in Tyler County

Direct sow Vinca (Annual) outdoors after March 06 in Tyler County when soil has warmed and frost danger has passed.

Sandy soil in Tyler County dries quickly — mulch Vinca (Annual) with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 →

Frequently Asked Questions

When should I plant Vinca (Annual) in Tyler County, TX?

Tyler County is in Zone 9a with an average last frost of March 6. Plan your Vinca (Annual) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tyler County, TX?

Tyler County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 6 and first fall frost is November 19.

🌱

Your Tyler County Garden Planner — Free

A 22-page printable planner built for Tyler 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Tyler County, TX. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.