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When to Plant Watercress in Rankin County, MS

Rankin County, Mississippi Zone 8b May

Your May planting checklist for Rankin County, Mississippi

A quick May briefing for Rankin County, Mississippi gardeners — what's urgent, what's next, and what can wait.

Avg. last frost March 17
Avg. first frost November 13
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. Basket week: 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.

Rankin County, Mississippi is in USDA Zone 8b. The average last spring frost is March 17 and the first fall frost is November 13, giving you a growing season of approximately 241 days.

At an elevation of 348 feet, Rankin County receives approximately 51.4 inches of rainfall annually with predominantly clay loam soil. Summer highs average 95°F, so Watercress may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Watercress, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watercress root diseases.

Rankin County, MS (Zone 8b) Long season
241 days
Last Spring Frost March 17
241 growing days
First Fall Frost November 13

Rankin County Soil Profile

Soil Type

Clay Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (166 days to spare)
Start indoors: Jan 30 Transplant: Mar 6 🍅 Harvest: Apr 17 – May 22
Recommended (50%) ✓ Fits season (164 days to spare)
Start indoors: Feb 10 Transplant: Mar 17 🍅 Harvest: Apr 28 – Jun 2
Safe Start (90%) ✓ Fits season (163 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 16 – Jun 20

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 Rankin County

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

Soil pH

Your soil pH (5.5–6.5) is more acidic than Watercress prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

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

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

7
successive plantings in your 241-day season

Sow every 4.6 weeks. Last sowing by Sep 14 to harvest before frost.

For a dedicated fall crop, sow by Sep 04.

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 1,296 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 4.3" 0" ❄️ Dormant
Feb 4" 0" ❄️ Dormant
Mar 6.5" 4.8" 1.7" 💧 Light watering
Apr 6.5" 4.1" 2.4" 💧 Light watering
May 6.5" 4" 2.5" 💧 Light watering
Jun 6.5" 5.1" 1.4" 💧 Light watering
Jul 6.5" 5.7" 0.8" 💧 Light watering
Aug 6.5" 4.3" 2.2" 💧 Light watering
Sep 6.5" 3.5" 3" 💧 Light watering
Oct 6.5" 3.4" 3.1" 💧 Light watering
Nov 6.5" 4.1" 2.4" 💧 Light watering
Dec 4.1" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Rankin 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 ~1,062 GDD — county provides 5,121 GDD Excellent fit

Watercress Planting Timeline — Rankin County, MS

Watercress Planting Calendar

Activity When Date Range
Start Indoors February 10 Feb 10 – Feb 24
Transplant Outdoors March 17 Mar 17 – Mar 31
Direct Sow March 3 Mar 3 – Mar 24
Harvest April 28 Apr 28 – Jun 2
Fall Sowing September 4 Sep 4 – Sep 18

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Transplant Outdoors Direct Sow
April Harvest
May Harvest
June Harvest
July
August
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 8b

📆 Growing Season

241 days in Rankin County

Growing Tips for Watercress in Rankin County

Direct sow Watercress outdoors after March 17 in Rankin County when soil has warmed and frost danger has passed.

With Rankin County's clay soil (28% clay), work in 3-4 inches of compost before planting Watercress. Avoid tilling when soil is wet to prevent compaction.

Your generous 241.0-day season in Rankin 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 Rankin County, MS?

Rankin County is in Zone 8b with an average last frost of March 17. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Rankin County, MS?

Rankin County, Mississippi is in USDA Hardiness Zone 8b. The average last spring frost is March 17 and first fall frost is November 13.

🌱

Your Rankin County Garden Planner — Free

A 24-page printable planner built for Rankin County (Zone 8b). 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 Rankin County, MS. 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.