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When to Plant Watercress in Nelson County, KY

Watercress is a semi-aquatic plant with a peppery, tangy flavor rich in vitamins and minerals. It grows naturally along streams and can be cultivated in containers with standing water.

Nelson County, Kentucky is in USDA Zone 6b. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.

At an elevation of 2,068 feet, Nelson County receives approximately 46.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Watercress during the growing season.

Nelson County, KY (Zone 6b) Long season
208 days
Last Spring Frost April 6
208 growing days
First Fall Frost October 31

Nelson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (134 days to spare)
Start indoors: Feb 22 Transplant: Mar 29 🍅 Harvest: May 10 – Jun 14
Recommended (50%) ✓ Fits season (131 days to spare)
Start indoors: Mar 2 Transplant: Apr 6 🍅 Harvest: May 18 – Jun 22
Safe Start (90%) ✓ Fits season (129 days to spare)
Start indoors: Mar 15 Transplant: Apr 19 🍅 Harvest: May 31 – Jul 5

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 Nelson County

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

Soil pH

Your soil pH (5.7โ€“7.0) is more acidic than Watercress prefers (6.5โ€“7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Nelson County is excellent for Watercress โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Watercress.

Organic Matter

Organic matter is moderate (2.4%). Annual compost additions will help Watercress.

How to Plant Watercress

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Watercress

6
successive plantings in your 208-day season

Sow every 4.6 weeks. Last sowing by Sep 01 to harvest before frost.

For a dedicated fall crop, sow by Aug 22.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 217 gal / 100 sq ft

Monthly Watering Guide for Watercress

Watercress needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Watercress Needs Rainfall You Supplement Action
Jan โ€” 4.2" 0" โ„๏ธ Dormant
Feb โ€” 3.3" 0" โ„๏ธ Dormant
Mar โ€” 4.8" 0" โ„๏ธ Dormant
Apr 6.5" 3.9" 2.6" ๐Ÿ’ง Light watering
May 6.5" 3.3" 3.2" ๐Ÿ’ง Light watering
Jun 6.5" 4" 2.5" ๐Ÿ’ง Light watering
Jul 6.5" 4.5" 2" ๐Ÿ’ง Light watering
Aug 6.5" 4.6" 1.9" ๐Ÿ’ง Light watering
Sep 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Oct 6.5" 3.2" 3.3" ๐Ÿšฟ Regular watering
Nov โ€” 3.9" 0" โ„๏ธ Dormant
Dec โ€” 3.2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Nelson County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Watercress 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" โ€” every day above 50ยฐF 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.

Watercress needs ~800 GDD — county provides 3,328 GDD Excellent fit

Watercress Planting Timeline โ€” Nelson County, KY

Watercress Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 โ€“ Mar 16
Transplant Outdoors April 6 Apr 6 โ€“ Apr 20
Direct Sow March 23 Mar 23 โ€“ Apr 13
Harvest May 18 May 18 โ€“ Jun 22
Fall Sowing August 22 Aug 22 โ€“ Sep 5

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July โ€”
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6.5โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

208 days in Nelson County

Growing Tips for Watercress in Nelson County

Direct sow Watercress outdoors after April 06 in Nelson County when soil has warmed and frost danger has passed.

Your generous 208.0-day season in Nelson County allows multiple plantings of Watercress. Sow every 20.0 days for continuous harvest.

Common pests for Watercress in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Grow in containers with trays of water kept fresh. Provide partial shade and cool conditions. Harvest stems by cutting above water level. Replace water frequently to prevent stagnation.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Watercress in Nelson County, KY?

Nelson County is in Zone 6b with an average last frost of April 6. Plan your Watercress planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Nelson County, KY?

Nelson County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 6 and first fall frost is October 31.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Nelson County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Nelson County, KY. Local conditions may vary. Last updated: April 2026.