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When to plant Nasturtium in Washington County County,

Plant Nasturtium in Washington County County after April 21; the prime window is April 28–May 19.

When to Plant Nasturtium in Washington County, KS

Washington County, Kansas Zone 6a June

June in the garden — Washington County, Kansas

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

Avg. last frost April 21
Avg. first frost October 14
Soil temp (4") 68°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Bring in the 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.

Washington County, Kansas is in USDA Zone 6a. The average last spring frost is April 21 and the first fall frost is October 14, giving you a growing season of approximately 176 days.

At an elevation of 562 feet, Washington County receives approximately 26.9 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Nasturtium to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Washington County, KS (Zone 6a) Moderate season
176 days
Last Spring Frost April 21
176 growing days
First Fall Frost October 14
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Washington County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.6

Drainage

Well Drained

Nasturtium Planting Risk Windows

Early Start (70% safe) ✓ Fits season (4 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🌸 Bloom: Jun 16 – Oct 6
Recommended (50%) ✓ Fits season (1 days to spare)
Start indoors: Mar 24 Transplant: Apr 28 🌸 Bloom: Jun 23 – Oct 13
Safe Start (90%) ✓ Fits season (2 days to spare)
Start indoors: Apr 5 Transplant: May 10 🌸 Bloom: Jul 5 – Oct 25

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 Washington County

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

Soil pH

Your soil pH (6.8–7.6) is within Nasturtium's preferred range (6.0–8.0).

Soil Texture

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

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Nasturtium.

How to Plant Nasturtium

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

Succession Planting Nasturtium

3
successive plantings in your 176-day season

Sow every 6.3 weeks. Last sowing by Aug 10 to harvest before frost.

Nasturtium Water Budget

Plant needs
0.5″/week
Rainfall provides
0.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 0.8" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 1.6" 0" ❄️ Dormant
Apr 2.2" 3.2" 0" ✅ Rainfall sufficient
May 2.2" 4" 0" ✅ Rainfall sufficient
Jun 2.2" 4" 0" ✅ Rainfall sufficient
Jul 2.2" 3.1" 0" ✅ Rainfall sufficient
Aug 2.2" 3.5" 0" ✅ Rainfall sufficient
Sep 2.2" 2.4" 0" ✅ Rainfall sufficient
Oct 2.2" 1.7" 0.5" 💧 Light watering
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Washington 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 ~780 GDD — county provides 2,288 GDD Excellent fit

Nasturtium Planting Timeline — Washington County, KS

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors March 24 Mar 24 – Apr 7
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow April 28 Apr 28 – May 19
Bloom June 23 Jun 23 – Oct 13

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December
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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 6a

📆 Growing Season

176 days in Washington County

Growing Tips for Nasturtium in Washington County

Direct sow Nasturtium outdoors after April 21 in Washington County when soil has warmed and frost danger has passed.

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 Washington County, KS?

Washington County is in Zone 6a with an average last frost of April 21. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, KS?

Washington County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 21 and first fall frost is October 14.

When should I plant Nasturtium in Washington County County, ?

In Washington County County, , plant Nasturtium after the last frost (around April 21) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is Washington County County, for Nasturtium?

Washington County County sits in USDA Zone 6a. Nasturtium grows reliably in zones 2a through 11b, so it's a good fit here.

Can Nasturtium grow in Washington County County's climate?

Yes — Nasturtium grows well in Washington County County's temperate climate. Washington County County averages a 176-day frost-free season, with last frost around April 21 and first frost around October 14.

🌱

Your Washington County Garden Planner — Free

A 22-page printable planner built for Washington County (Zone 6a). 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 Washington County, KS. 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.