When to Plant Nasturtium in Duval County, TX
June to-do list for Duval County, Texas
Here's what deserves your attention in Duval County, Texas this month. Everything below is tailored to Zone 9b and timed around your local frost dates.
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Start harvesting nasturtium
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
July prep starts now
- First harvests: nasturtium
Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.
Duval County, Texas is in USDA Zone 9b. The average last spring frost is February 13 and the first fall frost is December 9, giving you a growing season of approximately 299 days.
At an elevation of 4,259 feet, Duval County receives approximately 55.2 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Nasturtium may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Nasturtium root diseases.
Duval County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.3
Drainage
Well Drained
Nasturtium 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 Duval County
How your county's soil matches Nasturtium's growing requirements.
Soil pH
Your soil pH (6.8–7.3) is within Nasturtium's preferred range (6.0–8.0).
Soil Texture
The loam soil in Duval County is excellent for Nasturtium — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). Annual compost additions will help Nasturtium.
How to Plant Nasturtium
Succession Planting Nasturtium
Sow every 6.3 weeks. Last sowing by Oct 05 to harvest before frost.
Nasturtium Water Budget
Monthly Watering Guide for Nasturtium
Nasturtium 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 | Nasturtium Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | 2.2" | 1.7" | 0.5" | 💧 Light watering |
| Mar | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 5.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 8.7" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 8.4" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 6.8" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 6" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 5.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Dec | 2.2" | 1.6" | 0.6" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Duval County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Nasturtium 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.
Nasturtium Planting Timeline — Duval County, TX
Nasturtium Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 16 | Jan 16 – Jan 30 |
| Transplant Outdoors | January 16 | Jan 16 – Jan 30 |
| Direct Sow | January 16 | Jan 16 – Feb 6 |
| Bloom | March 13 | Mar 13 – Sep 25 |
Plant 0.5" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Transplant Outdoors Direct Sow |
| February | 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
55–65 days
🧪 Soil pH
Needs 6–8 · Your soil: ideal
🗺️ USDA Zone
Zone 9b
📆 Growing Season
299 days in Duval County
Growing Tips for Nasturtium in Duval County
Direct sow Nasturtium outdoors after February 13 in Duval County when soil has warmed and frost danger has passed.
With summer highs reaching 102°F in Duval County, provide afternoon shade for Nasturtium and water deeply in the morning.
General growing tips
Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Nasturtium in Other Locations
Frequently Asked Questions
When should I plant Nasturtium in Duval County, TX?
Duval County is in Zone 9b with an average last frost of February 13. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.
What planting zone is Duval County, TX?
Duval County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 13 and first fall frost is December 9.
Your Duval County Garden Planner — Free
A 22-page printable planner built for Duval 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.