Blog

When to Plant Watercress in Houghton County, MI

Houghton County, Michigan Zone 5b May

Top priorities for Houghton County, Michigan gardeners in May

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost May 19
Avg. first frost October 2
Soil temp (4") 54°F
Watering Low
Pest pressure Low
Daylight 14.9 hrs
  1. Move watercress from tray to bed

    Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.

  2. Seed watercress outdoors

    Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.

June will be here before you know it — start on
  • Starting indoors: watercress
  • First harvests: watercress

Instant PDF download. No spam, unsubscribe any time.

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.

Houghton County, Michigan is in USDA Zone 5b. The average last spring frost is May 19 and the first fall frost is October 2, giving you a growing season of approximately 136 days.

At an elevation of 956 feet, Houghton County receives approximately 34.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Watercress to ensure they mature before fall.

Houghton County, MI (Zone 5b) Short season
136 days
Last Spring Frost May 19
136 growing days
First Fall Frost October 2

Houghton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (59 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jun 26 – Jul 31
Recommended (50%) ✓ Fits season (59 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 30 – Aug 4
Safe Start (90%) ✓ Fits season (63 days to spare)
Start indoors: Apr 28 Transplant: Jun 2 🍅 Harvest: Jul 14 – Aug 18

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 Houghton County

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

Soil pH

Your soil pH (5.9–7.2) overlaps with Watercress's range (6.5–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). 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 136-day season

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

For a dedicated fall crop, sow by Jul 24.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.1″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 526 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 1.3" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 3.6" 0" ❄️ Dormant
May 6.5" 3.8" 2.7" 💧 Light watering
Jun 6.5" 4.2" 2.3" 💧 Light watering
Jul 6.5" 3.3" 3.2" 💧 Light watering
Aug 6.5" 3.5" 3" 💧 Light watering
Sep 6.5" 3.4" 3.1" 💧 Light watering
Oct 6.5" 2.9" 3.6" 🚿 Regular watering
Nov 2.1" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Houghton 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 ~650 GDD — county provides 1,768 GDD Excellent fit

Watercress Planting Timeline — Houghton County, MI

Watercress Planting Calendar

Activity When Date Range
Start Indoors April 14 Apr 14 – Apr 28
Transplant Outdoors May 19 May 19 – Jun 2
Direct Sow May 5 May 5 – May 26
Harvest June 30 Jun 30 – Aug 4
Fall Sowing July 24 Jul 24 – Aug 7

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May Transplant Outdoors Direct Sow
June Transplant Outdoors Harvest
July Fall Sowing Harvest
August Fall Sowing Harvest
September
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: acceptable

🗺️ USDA Zone

Zone 5b

📆 Growing Season

136 days in Houghton County

Growing Tips for Watercress in Houghton County

Direct sow Watercress outdoors after May 19 in Houghton 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.

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 Houghton County, MI?

Houghton County is in Zone 5b with an average last frost of May 19. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Houghton County, MI?

Houghton County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 19 and first fall frost is October 2.

🌱

Your Houghton County Garden Planner — Free

A 24-page printable planner built for Houghton County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Houghton County, MI. 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.