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When to Plant Watercress in Murray County, OK

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.

Murray County, Oklahoma is in USDA Zone 7b. The average last spring frost is March 28 and the first fall frost is November 2, giving you a growing season of approximately 219 days.

At an elevation of 640 feet, Murray County receives approximately 23.2 inches of rainfall annually with predominantly loam soil. Summer highs average 94ยฐF, providing good warmth for Watercress during the growing season.

Murray County, OK (Zone 7b) Long season
219 days
Last Spring Frost March 28
219 growing days
First Fall Frost November 2

Murray County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (144 days to spare)
Start indoors: Feb 14 Transplant: Mar 21 🍅 Harvest: May 2 – Jun 6
Recommended (50%) ✓ Fits season (142 days to spare)
Start indoors: Feb 21 Transplant: Mar 28 🍅 Harvest: May 9 – Jun 13
Safe Start (90%) ✓ Fits season (143 days to spare)
Start indoors: Mar 13 Transplant: Apr 17 🍅 Harvest: May 29 – Jul 3

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 Murray County

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

Soil pH

Your soil pH (6.5โ€“7.7) overlaps with Watercress's range (6.5โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) โ€” Watercress will thrive.

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 219-day season

Sow every 4.6 weeks. Last sowing by Sep 03 to harvest before frost.

For a dedicated fall crop, sow by Aug 24.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.4″/week
You supply
1.3″/week
Watering frequency 2-3 times/week
Season total 2,468 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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€” 0.6" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar 6.5" 1.4" 5.1" ๐Ÿšฟ Regular watering
Apr 6.5" 2.3" 4.2" ๐Ÿšฟ Regular watering
May 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Jun 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Jul 6.5" 2.8" 3.7" ๐Ÿšฟ Regular watering
Aug 6.5" 3.1" 3.4" ๐Ÿšฟ Regular watering
Sep 6.5" 2.3" 4.2" ๐Ÿšฟ Regular watering
Oct 6.5" 1.4" 5.1" ๐Ÿšฟ Regular watering
Nov 6.5" 0.8" 5.7" ๐Ÿšฟ Regular watering
Dec โ€” 0.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Murray 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 ~1,025 GDD — county provides 4,489 GDD Excellent fit

Watercress Planting Timeline โ€” Murray County, OK

Watercress Planting Calendar

Activity When Date Range
Start Indoors February 21 Feb 21 โ€“ Mar 7
Transplant Outdoors March 28 Mar 28 โ€“ Apr 11
Direct Sow March 14 Mar 14 โ€“ Apr 4
Harvest May 9 May 9 โ€“ Jun 13
Fall Sowing August 24 Aug 24 โ€“ Sep 7

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

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors Transplant Outdoors 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 2-3 times/week

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6.5โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

219 days in Murray County

Growing Tips for Watercress in Murray County

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

Your generous 219.0-day season in Murray 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.

Murray County receives only 23" of rain annually. Watercress needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

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 Murray County, OK?

Murray County is in Zone 7b with an average last frost of March 28. Plan your Watercress planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Murray County, OK?

Murray County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is March 28 and first fall frost is November 2.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Murray County gardeners in Zone 7b 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 Murray County, OK. Local conditions may vary. Last updated: April 2026.