Blog

When to Plant Watercress in Logan County, CO

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.

Logan County, Colorado is in USDA Zone 5a. The average last spring frost is May 11 and the first fall frost is October 5, giving you a growing season of approximately 147 days.

At an elevation of 6,511 feet, Logan County receives approximately 14.9 inches of rainfall annually with predominantly loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Watercress to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Watercress successfully. Mulch heavily to conserve soil moisture.

Logan County, CO (Zone 5a) Short season
147 days
Last Spring Frost May 11
147 growing days
First Fall Frost October 5

Logan County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (76 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 13 – Jul 18
Recommended (50%) ✓ Fits season (70 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jun 22 – Jul 27
Safe Start (90%) ✓ Fits season (70 days to spare)
Start indoors: Apr 16 Transplant: May 21 🍅 Harvest: Jul 2 – Aug 6

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 Logan County

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

Soil pH

Your soil pH (6.4โ€“7.9) overlaps with Watercress's range (6.5โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). 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

4
successive plantings in your 147-day season

Sow every 4.6 weeks. Last sowing by Aug 06 to harvest before frost.

For a dedicated fall crop, sow by Jul 27.

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 1,687 gal / 100 sq ft
Drought risk

Water stress score is 8/10 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€” 1" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 1.1" 0" โ„๏ธ Dormant
Apr โ€” 1.6" 0" โ„๏ธ Dormant
May 6.5" 1.7" 4.8" ๐Ÿšฟ Regular watering
Jun 6.5" 1.2" 5.3" ๐Ÿšฟ Regular watering
Jul 6.5" 1.3" 5.2" ๐Ÿšฟ Regular watering
Aug 6.5" 1.5" 5" ๐Ÿšฟ Regular watering
Sep 6.5" 1.3" 5.2" ๐Ÿšฟ Regular watering
Oct 6.5" 1.3" 5.2" ๐Ÿšฟ Regular watering
Nov โ€” 1.1" 0" โ„๏ธ Dormant
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Logan 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 ~612 GDD — county provides 1,800 GDD Excellent fit

Watercress Planting Timeline โ€” Logan County, CO

Watercress Planting Calendar

Activity When Date Range
Start Indoors April 6 Apr 6 โ€“ Apr 20
Transplant Outdoors May 11 May 11 โ€“ May 25
Direct Sow April 27 Apr 27 โ€“ May 18
Harvest June 22 Jun 22 โ€“ Jul 27
Fall Sowing July 27 Jul 27 โ€“ Aug 10

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August Fall Sowing
September โ€”
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 5a

๐Ÿ“† Growing Season

147 days in Logan County

Growing Tips for Watercress in Logan County

Direct sow Watercress outdoors after May 11 in Logan County when soil has warmed and frost danger has passed.

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

Logan County receives only 15" 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 Logan County, CO?

Logan County is in Zone 5a with an average last frost of May 11. Plan your Watercress planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Logan County, CO?

Logan County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is May 11 and first fall frost is October 5.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Logan County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Logan County, CO. Local conditions may vary. Last updated: April 2026.