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When to Plant Cress in Dewey County, SD

Dewey County, South Dakota Zone 4b May

This month in Dewey County, South Dakota

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 11
Avg. first frost October 3
Soil temp (4") 56°F
Watering Moderate
Pest pressure Low
Daylight 14.7 hrs
  1. Move cress into the garden

    Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.

  2. Scatter cress into prepared beds

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

  3. Harvest cress as they ripen

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Looking ahead to June
  • 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.

Dewey County, South Dakota is in USDA Zone 4b. The average last spring frost is May 11 and the first fall frost is October 3, giving you a growing season of approximately 145 days.

At an elevation of 1,004 feet, Dewey County receives approximately 25.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Cress to ensure they mature before fall.

Dewey County, SD (Zone 4b) Short season
145 days
Last Spring Frost May 11
145 growing days
First Fall Frost October 3
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Dewey County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (113 days to spare)
Start indoors: Mar 21 Transplant: May 2 🍅 Harvest: May 16 – Jun 6
Recommended (50%) ✓ Fits season (110 days to spare)
Start indoors: Mar 30 Transplant: May 11 🍅 Harvest: May 25 – Jun 15
Safe Start (90%) ✓ Fits season (115 days to spare)
Start indoors: Apr 7 Transplant: May 19 🍅 Harvest: Jun 2 – Jun 23

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 Dewey County

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

Soil pH

Your soil pH (6.2–7.6) overlaps with Cress's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Cress.

How to Plant Cress

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Cress

12
successive plantings in your 145-day season

Sow every 1.6 weeks. Last sowing by Sep 12 to harvest before frost.

For a dedicated fall crop, sow by Jul 11.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 418 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 1.5" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 2.9" 0" ❄️ Dormant
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 1.8" 2.5" 🚿 Regular watering
Jul 4.3" 2.1" 2.2" 🚿 Regular watering
Aug 4.3" 2.8" 1.5" 💧 Light watering
Sep 4.3" 2.3" 2" 💧 Light watering
Oct 4.3" 2.3" 2" 💧 Light watering
Nov 1.5" 0" ❄️ Dormant
Dec 1.4" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Dewey 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 ~228 GDD — county provides 1,885 GDD Excellent fit

Cress Planting Timeline — Dewey County, SD

Cress Planting Calendar

Activity When Date Range
Start Indoors March 30 Mar 30 – Apr 13
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 4 May 4 – May 25
Harvest May 25 May 25 – Jun 15
Fall Sowing July 11 Jul 11 – Jul 25

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

14–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 4b

📆 Growing Season

145 days in Dewey County

Growing Tips for Cress in Dewey County

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

Your generous 145.0-day season in Dewey 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 Dewey County, SD?

Dewey County is in Zone 4b with an average last frost of May 11. Plan your Cress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dewey County, SD?

Dewey County, South Dakota is in USDA Hardiness Zone 4b. The average last spring frost is May 11 and first fall frost is October 3.

🌱

Your Dewey County Garden Planner — Free

A 24-page printable planner built for Dewey County (Zone 4b). 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 Dewey County, SD. Local conditions may vary. Last updated: May 2026.

Sources & credits

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