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When to Plant Nasturtium in McClain County, OK

McClain County, Oklahoma Zone 7b June

June in the garden — McClain County, Oklahoma

Your McClain County, Oklahoma garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost April 2
Avg. first frost November 5
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Basket week: nasturtium

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Before July arrives, get these ready
  • 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.

McClain County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is November 5, giving you a growing season of approximately 217 days.

At an elevation of 558 feet, McClain County receives approximately 23.4 inches of rainfall annually with predominantly loam soil. Summer highs average 94°F, providing good warmth for Nasturtium during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
McClain County, OK (Zone 7b) Long season
217 days
Last Spring Frost April 2
217 growing days
First Fall Frost November 5

McClain County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.8

Drainage

Well Drained

Nasturtium Planting Risk Windows

Early Start (70% safe) ✓ Fits season (26 days to spare)
Start indoors: Feb 21 Transplant: Mar 21 🌸 Bloom: May 16 – Oct 3
Recommended (50%) ✓ Fits season (21 days to spare)
Start indoors: Mar 5 Transplant: Apr 2 🌸 Bloom: May 28 – Oct 15
Safe Start (90%) ✓ Fits season (24 days to spare)
Start indoors: Mar 18 Transplant: Apr 15 🌸 Bloom: Jun 10 – Oct 28

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 McClain County

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

Soil pH

Your soil pH (6.4–7.8) is within Nasturtium's preferred range (6.0–8.0).

Soil Texture

The loam soil in McClain County is excellent for Nasturtium — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Nasturtium.

How to Plant Nasturtium

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

Succession Planting Nasturtium

4
successive plantings in your 217-day season

Sow every 6.3 weeks. Last sowing by Sep 01 to harvest before frost.

Nasturtium Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 109 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 0.6" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 1.3" 0" ❄️ Dormant
Apr 2.2" 2.7" 0" ✅ Rainfall sufficient
May 2.2" 3" 0" ✅ Rainfall sufficient
Jun 2.2" 3.8" 0" ✅ Rainfall sufficient
Jul 2.2" 2.9" 0" ✅ Rainfall sufficient
Aug 2.2" 3.1" 0" ✅ Rainfall sufficient
Sep 2.2" 2.3" 0" ✅ Rainfall sufficient
Oct 2.2" 1.5" 0.7" 💧 Light watering
Nov 2.2" 0.9" 1.3" 🚿 Regular watering
Dec 0.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in McClain 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 ~1,230 GDD — county provides 4,448 GDD Excellent fit

Nasturtium Planting Timeline — McClain County, OK

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors April 2 Apr 2 – Apr 16
Direct Sow April 2 Apr 2 – Apr 23
Bloom May 28 May 28 – Oct 15

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
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 · Only during dry spells

📅 Days to Maturity

55–65 days

🧪 Soil pH

Needs 6–8 · Your soil: ideal

🗺️ USDA Zone

Zone 7b

📆 Growing Season

217 days in McClain County

Growing Tips for Nasturtium in McClain County

Direct sow Nasturtium outdoors after April 02 in McClain County when soil has warmed and frost danger has passed.

McClain County receives only 23" of rain annually. Nasturtium needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 McClain County, OK?

McClain County is in Zone 7b with an average last frost of April 2. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.

What planting zone is McClain County, OK?

McClain County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is November 5.

🌱

Your McClain County Garden Planner — Free

A 22-page printable planner built for McClain County (Zone 7b). 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 McClain County, OK. 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.