When to Plant Zinnia in Refugio County, TX
This month in Refugio County, Texas
July is a pivotal month for Refugio County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Collect zinnia at their peak
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
August prep starts now
- First harvests: zinnia
Zinnia (Zinnia elegans) is a fast-growing, heat-loving annual that produces bold, dahlia-like blooms from early summer until hard frost. One of the easiest flowers to grow from direct-sown seed, zinnias thrive in hot, dry conditions and are magnets for butterflies and beneficial insects. They make excellent companion plants alongside marigolds in the vegetable garden.
Refugio County, Texas is in USDA Zone 9b. The average last spring frost is February 16 and the first fall frost is December 6, giving you a growing season of approximately 293 days.
At an elevation of 1,000 feet, Refugio County receives approximately 68.4 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Zinnia may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Zinnia root diseases.
Refugio County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.2
Drainage
Well Drained
Zinnia 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 Refugio County
How your county's soil matches Zinnia's growing requirements.
Soil pH
Your soil pH (6.7–7.2) is within Zinnia's preferred range (5.5–7.5).
Soil Texture
The loam soil in Refugio County is excellent for Zinnia — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.0%). Annual compost additions will help Zinnia.
How to Plant Zinnia
Succession Planting Zinnia
Sow every 6.9 weeks. Last sowing by Sep 27 to harvest before frost.
Zinnia Water Budget
Monthly Watering Guide for Zinnia
Zinnia 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 | Zinnia Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2" | 0" | ❄️ Dormant |
| Feb | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Mar | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 8.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 9.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 11.3" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 9.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 5.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Dec | 2.2" | 1.8" | 0.4" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Refugio County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Zinnia 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.
Zinnia Planting Timeline — Refugio County, TX
Zinnia Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 19 | Jan 19 – Feb 2 |
| Transplant Outdoors | January 19 | Jan 19 – Feb 2 |
| Direct Sow | January 19 | Jan 19 – Feb 9 |
| Bloom | March 30 | Mar 30 – Sep 28 |
Plant 0.3" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Transplant Outdoors Direct Sow |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Bloom |
| April | Bloom |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
60–70 days
🧪 Soil pH
Needs 5.5–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 9b
📆 Growing Season
293 days in Refugio County
Growing Tips for Zinnia in Refugio County
Direct sow Zinnia outdoors after February 16 in Refugio County when soil has warmed and frost danger has passed.
With summer highs reaching 103°F in Refugio County, provide afternoon shade for Zinnia and water deeply in the morning.
Common pests for Zinnia in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct-sow after last frost when soil reaches 60°F; seeds germinate in 5-7 days. In zones 3-5 a brief indoor start (4 weeks) is worthwhile but transplant carefully — zinnias dislike root disturbance. Deadhead frequently to extend bloom. Excellent cut flower; harvesting regularly encourages branching. Avoid overhead watering to reduce powdery mildew.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Zinnia in Other Locations
Frequently Asked Questions
When should I plant Zinnia in Refugio County, TX?
Refugio County is in Zone 9b with an average last frost of February 16. Plan your Zinnia planting based on this frost date — see the calendar above for exact timing.
What planting zone is Refugio County, TX?
Refugio County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 16 and first fall frost is December 6.
Your Refugio County Garden Planner — Free
A 22-page printable planner built for Refugio County (Zone 9b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.