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When to Plant Watercress in Carlisle County, KY

Carlisle County, Kentucky Zone 7a May

This month in Carlisle County, Kentucky

Your garden in Carlisle County, Kentucky is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost March 28
Avg. first frost October 31
Soil temp (4") 54°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs
  1. Begin indoor sowing: watercress

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Harvest watercress as they ripen

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Get ahead of June
  • First harvests: watercress

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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.

Carlisle County, Kentucky is in USDA Zone 7a. The average last spring frost is March 28 and the first fall frost is October 31, giving you a growing season of approximately 217 days.

At an elevation of 4,000 feet, Carlisle County receives approximately 44.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Watercress during the growing season.

Carlisle County, KY (Zone 7a) Long season
217 days
Last Spring Frost March 28
217 growing days
First Fall Frost October 31

Carlisle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (143 days to spare)
Start indoors: Feb 12 Transplant: Mar 19 🍅 Harvest: Apr 30 – Jun 4
Recommended (50%) ✓ Fits season (140 days to spare)
Start indoors: Feb 21 Transplant: Mar 28 🍅 Harvest: May 9 – Jun 13
Safe Start (90%) ✓ Fits season (134 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 27 – Jul 1

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 Carlisle County

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

Soil pH

Your soil pH (5.7–6.7) is more acidic than Watercress prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Carlisle County is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). 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 217-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
0.6″/week
Watering frequency 1-2 times/week
Season total 1,230 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 4" 0" ❄️ Dormant
Feb 3.9" 0" ❄️ Dormant
Mar 6.5" 4.1" 2.4" 💧 Light watering
Apr 6.5" 3.4" 3.1" 💧 Light watering
May 6.5" 3.7" 2.8" 💧 Light watering
Jun 6.5" 3.6" 2.9" 💧 Light watering
Jul 6.5" 4.8" 1.7" 💧 Light watering
Aug 6.5" 4.3" 2.2" 💧 Light watering
Sep 6.5" 3.2" 3.3" 🚿 Regular watering
Oct 6.5" 2.6" 3.9" 🚿 Regular watering
Nov 3.2" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Oct in Carlisle County). Supplement amounts are based on average rainfall — 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" — 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.

Watercress needs ~875 GDD — county provides 3,797 GDD Excellent fit

Watercress Planting Timeline — Carlisle County, KY

Watercress Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 – Mar 7
Transplant Outdoors March 28 Mar 28 – Apr 11
Direct Sow March 14 Mar 14 – Apr 4
Harvest May 9 May 9 – Jun 13
Fall Sowing August 22 Aug 22 – Sep 5

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 1-2 times/week

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

217 days in Carlisle County

Growing Tips for Watercress in Carlisle County

Direct sow Watercress outdoors after March 28 in Carlisle County when soil has warmed and frost danger has passed.

Your generous 217.0-day season in Carlisle 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 Carlisle County, KY?

Carlisle County is in Zone 7a with an average last frost of March 28. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Carlisle County, KY?

Carlisle County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is March 28 and first fall frost is October 31.

🌱

Your Carlisle County Garden Planner — Free

A 24-page printable planner built for Carlisle County (Zone 7a). 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 Carlisle County, KY. Local conditions may vary. Last updated: May 2026.

Sources & credits

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