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When to Plant Nasturtium in Tarrant County, TX

Tarrant County, Texas Zone 8b June

Tarrant County, Texas gardeners: here's your June plan

Your garden in Tarrant County, Texas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost March 18
Avg. first frost November 12
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 14.1 hrs
  1. Start harvesting nasturtium

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

July will be here before you know it — start on
  • First harvests: nasturtium

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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.

Tarrant County, Texas is in USDA Zone 8b. The average last spring frost is March 18 and the first fall frost is November 12, giving you a growing season of approximately 239 days.

At an elevation of 3,487 feet, Tarrant County receives approximately 63.1 inches of rainfall annually with predominantly clay soil. Summer highs average 92°F, providing good warmth for Nasturtium during the growing season. Clay soil retains moisture well for Nasturtium, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Nasturtium root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Tarrant County, TX (Zone 8b) Long season
239 days
Last Spring Frost March 18
239 growing days
First Fall Frost November 12

Tarrant County Soil Profile

Soil Type

Clay

Soil pH

7.3-8.1

Drainage

Well Drained

Nasturtium Planting Risk Windows

Early Start (70% safe) ✓ Fits season (37 days to spare)
Start indoors: Feb 6 Transplant: Feb 20 🌸 Bloom: Apr 17 – Oct 2
Recommended (50%) ✓ Fits season (29 days to spare)
Start indoors: Feb 18 Transplant: Mar 4 🌸 Bloom: Apr 29 – Oct 14
Safe Start (90%) ✓ Fits season (26 days to spare)
Start indoors: Mar 15 Transplant: Mar 29 🌸 Bloom: May 24 – Nov 8

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 Tarrant County

How your county's soil matches Nasturtium's growing requirements.

Soil pH

Your soil pH (7.3–8.1) overlaps with Nasturtium's range (6.0–8.0), though not a perfect match.

Soil Texture

Heavy clay soil (45% clay) in Tarrant County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Nasturtium.

How to Plant Nasturtium

0.5"
Planting Depth
10"
Between Plants
12"
Between Rows

Succession Planting Nasturtium

5
successive plantings in your 239-day season

Sow every 6.3 weeks. Last sowing by Sep 08 to harvest before frost.

Nasturtium Water Budget

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

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 1.8" 0" ❄️ Dormant
Feb 2.2" 0" ❄️ Dormant
Mar 2.2" 3.8" 0" ✅ Rainfall sufficient
Apr 2.2" 7" 0" ✅ Rainfall sufficient
May 2.2" 9.8" 0" ✅ Rainfall sufficient
Jun 2.2" 10.1" 0" ✅ Rainfall sufficient
Jul 2.2" 7.2" 0" ✅ Rainfall sufficient
Aug 2.2" 8.1" 0" ✅ Rainfall sufficient
Sep 2.2" 5.5" 0" ✅ Rainfall sufficient
Oct 2.2" 4.1" 0" ✅ Rainfall sufficient
Nov 2.2" 2.2" 0" ✅ Rainfall sufficient
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Tarrant 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 needs ~1,140 GDD — county provides 4,541 GDD Excellent fit

Nasturtium Planting Timeline — Tarrant County, TX

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors March 4 Mar 4 – Mar 18
Direct Sow March 4 Mar 4 – Mar 25
Bloom April 29 Apr 29 – Oct 14

Plant 0.5" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Bloom
May Bloom
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

55–65 days

🧪 Soil pH

Needs 6–8 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

239 days in Tarrant County

Growing Tips for Nasturtium in Tarrant County

Direct sow Nasturtium outdoors after March 18 in Tarrant County when soil has warmed and frost danger has passed.

With Tarrant County's clay soil (45% clay), work in 3-4 inches of compost before planting Nasturtium. Avoid tilling when soil is wet to prevent compaction.

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

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Nasturtium in Tarrant County, TX?

Tarrant County is in Zone 8b with an average last frost of March 18. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tarrant County, TX?

Tarrant County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 18 and first fall frost is November 12.

🌱

Your Tarrant County Garden Planner — Free

A 22-page printable planner built for Tarrant County (Zone 8b). 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 Tarrant County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

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