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When to plant Nasturtium in Clark County, KY

Nasturtium planted in Clark County between April 16 and May 7 matures in 55–65 days — well before the October 24 first frost.

When to Plant Nasturtium in Clark County, KY

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.

Clark County, Kentucky is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 24, giving you a growing season of approximately 191 days.

At an elevation of 3,545 feet, Clark County receives approximately 50.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Nasturtium during the growing season. 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
Clark County, KY (Zone 6b) Moderate season
191 days
Last Spring Frost April 16
191 growing days
First Fall Frost October 24

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Monthly Watering Guide for Nasturtium

Nasturtium needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Nasturtium Needs Rainfall You Supplement Action
Jan 4.6" 0" ❄️ Dormant
Feb 3.8" 0" ❄️ Dormant
Mar 4.7" 0" ❄️ Dormant
Apr 4.3" 4.2" 0.1" 💧 Light watering
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4.8" 0" ✅ Rainfall sufficient
Aug 4.3" 4.4" 0" ✅ Rainfall sufficient
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 4.1" 0" ❄️ Dormant
Dec 4.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Clark County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Nasturtium Planting Timeline — Clark County, KY

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors March 19 Mar 19 – Apr 2
Transplant Outdoors April 16 Apr 16 – Apr 30
Direct Sow April 16 Apr 16 – May 7
Bloom June 11 Jun 11 – Oct 8

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 Direct Sow
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

55–65 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

191 days in Clark County

Growing Tips for Clark County

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 Clark County, KY?

Clark County is in Zone 6b with an average last frost of April 16. Plan your Nasturtium planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clark County, KY?

Clark County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 24.

When should I plant Nasturtium in Clark County, KY?

In Clark County, KY, plant Nasturtium after the last frost (around April 16) and before the first frost (around October 24). Best results when soil holds above 50°F.

What growing zone is Clark County, KY for Nasturtium?

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

Can Nasturtium grow in Clark County's climate?

Yes — Nasturtium grows well in Clark County's temperate climate. Clark County averages a 191-day frost-free season, with last frost around April 16 and first frost around October 24.

🌱

Your Clark County Garden Planner — Free

A 22-page printable planner built for Clark County (Zone 6b). 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 Clark County, KY. Local conditions may vary. Last updated: July 2026.

Sources & credits

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