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When to Plant Cress in Pierce County, WA

Garden cress is one of the fastest-growing edibles, producing peppery sprouts in as little as two weeks. It is excellent for microgreens and garnishes.

Pierce County, Washington is in USDA Zone 8a. The average last spring frost is April 13 and the first fall frost is October 30, giving you a growing season of approximately 200 days.

At an elevation of 168 feet, Pierce County receives approximately 48.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Cress to ensure they mature before fall.

Pierce County, WA (Zone 8a) Long season
200 days
Last Spring Frost April 13
200 growing days
First Fall Frost October 30

Pierce County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (157 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: Apr 18 – May 9
Recommended (50%) ✓ Fits season (165 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Apr 27 – May 18
Safe Start (90%) ✓ Fits season (157 days to spare)
Start indoors: Apr 11 Transplant: May 16 🍅 Harvest: May 30 – 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 Pierce County

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

Soil pH

Your soil pH (5.4โ€“6.2) is more acidic than Cress prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.4%) โ€” Cress will thrive.

How to Plant Cress

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Cress

17
successive plantings in your 200-day season

Sow every 1.6 weeks. Last sowing by Oct 09 to harvest before frost.

For a dedicated fall crop, sow by Aug 21.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Cress

Cress needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Cress Needs Rainfall You Supplement Action
Jan โ€” 6.8" 0" โ„๏ธ Dormant
Feb โ€” 5.7" 0" โ„๏ธ Dormant
Mar โ€” 4.4" 0" โ„๏ธ Dormant
Apr 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
May 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Jun 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Jul 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Aug 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Sep 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Oct 4.3" 4.7" 0" โœ… Rainfall sufficient
Nov โ€” 7.8" 0" โ„๏ธ Dormant
Dec โ€” 6.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Pierce County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Cress 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.

Cress needs ~214 GDD — county provides 2,450 GDD Excellent fit

Cress Planting Timeline โ€” Pierce County, WA

Cress Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 โ€“ Mar 23
Transplant Outdoors April 13 Apr 13 โ€“ Apr 27
Direct Sow March 30 Mar 30 โ€“ Apr 20
Harvest April 27 Apr 27 โ€“ May 18
Fall Sowing August 21 Aug 21 โ€“ Sep 4

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow Harvest
May Harvest
June โ€”
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"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

14โ€“21 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

200 days in Pierce County

Growing Tips for Cress in Pierce County

Direct sow Cress outdoors after April 13 in Pierce County when soil has warmed and frost danger has passed.

Your generous 200.0-day season in Pierce County allows multiple plantings of Cress. Sow every 7.0 days for continuous harvest.

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

General growing tips

Sow seeds thickly on moist soil or paper towels. Keep moist and harvest when 2-3 inches tall. Succession sow every few days for continuous supply. Grows well indoors year-round.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cress in Pierce County, WA?

Pierce County is in Zone 8a with an average last frost of April 13. Plan your Cress planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pierce County, WA?

Pierce County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is April 13 and first fall frost is October 30.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pierce County gardeners in Zone 8a 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 Pierce County, WA. Local conditions may vary. Last updated: April 2026.