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When to Plant Cress in Harney County, OR

Harney County, Oregon Zone 6a June

This month in Harney County, Oregon

Here's what deserves your attention in Harney County, Oregon this month. Everything below is tailored to Zone 6a and timed around your local frost dates.

Avg. last frost June 17
Avg. first frost September 6
Soil temp (4") 70°F
Watering Critical
Pest pressure High
Daylight 15.2 hrs
  1. Move cress into the garden

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

  2. Scatter cress into prepared beds

    Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.

  3. Start your fall crops: cress

    Mid-season soil is hot. Sow a bit deeper than the packet suggests to find cooler, damper ground.

Get ahead of July
  • Starting indoors: cress
  • First harvests: cress

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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.

Harney County, Oregon is in USDA Zone 6a. The average last spring frost is June 17 and the first fall frost is September 6, giving you a growing season of approximately 81 days.

At an elevation of 679 feet, Harney County receives approximately 22.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Cress during the growing season.

Harney County, OR (Zone 6a) Very short season
81 days
Last Spring Frost June 17
81 growing days
First Fall Frost September 6
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Harney County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.4

Drainage

Well Drained

Cress Planting Risk Windows

Early Start (70% safe) ✓ Fits season (44 days to spare)
Start indoors: May 8 Transplant: Jun 12 🍅 Harvest: Jun 26 – Jul 17
Recommended (50%) ✓ Fits season (46 days to spare)
Start indoors: May 13 Transplant: Jun 17 🍅 Harvest: Jul 1 – Jul 22
Safe Start (90%) ✓ Fits season (58 days to spare)
Start indoors: May 20 Transplant: Jun 24 🍅 Harvest: Jul 8 – Jul 29

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 Harney County

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

Soil pH

Your soil pH (5.6–6.4) overlaps with Cress's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.5%) — 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

7
successive plantings in your 81-day season

Sow every 1.6 weeks. Last sowing by Aug 16 to harvest before frost.

For a dedicated fall crop, sow by Jun 28.

Cress Water Budget

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

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 3.3" 0" ❄️ Dormant
Feb 2.2" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 1.4" 0" ❄️ Dormant
Jun 4.3" 0.9" 3.4" 🚿 Regular watering
Jul 4.3" 0.4" 3.9" 🚿 Regular watering
Aug 4.3" 0.4" 3.9" 🚿 Regular watering
Sep 4.3" 0.9" 3.4" 🚿 Regular watering
Oct 2" 0" ❄️ Dormant
Nov 3.6" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Harney County). Supplement amounts are based on average rainfall — 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" — 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.

Cress needs ~267 GDD — county provides 1,235 GDD Excellent fit

Cress Planting Timeline — Harney County, OR

Cress Planting Calendar

Activity When Date Range
Start Indoors May 13 May 13 – May 27
Transplant Outdoors June 17 Jun 17 – Jul 1
Direct Sow June 3 Jun 3 – Jun 24
Harvest July 1 Jul 1 – Jul 22
Fall Sowing June 28 Jun 28 – Jul 12

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Start Indoors
June Transplant Outdoors Direct Sow Fall Sowing
July Transplant Outdoors Fall Sowing Harvest
August
September
October
November
December
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Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

14–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

81 days in Harney County

Growing Tips for Cress in Harney County

Direct sow Cress outdoors after June 17 in Harney County when soil has warmed and frost danger has passed.

Your generous 81.0-day season in Harney 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.

Harney County receives only 22" of rain annually. Cress needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Harney County, OR?

Harney County is in Zone 6a with an average last frost of June 17. Plan your Cress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Harney County, OR?

Harney County, Oregon is in USDA Hardiness Zone 6a. The average last spring frost is June 17 and first fall frost is September 6.

🌱

Your Harney County Garden Planner — Free

A 22-page printable planner built for Harney County (Zone 6a). 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 Harney County, OR. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.