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When to Plant Cress in Hamilton County, IL

Hamilton County, Illinois Zone 6b May

Your May gardening checklist

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

Avg. last frost April 9
Avg. first frost October 23
Soil temp (4") 63°F
Watering Low
Pest pressure Low
Daylight 14.1 hrs
  1. Get cress seeds going inside

    You're about 24 weeks out from your last frost — the perfect window to get these germinating indoors.

  2. It's harvest week for cress

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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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.

Hamilton County, Illinois is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 23, giving you a growing season of approximately 197 days.

At an elevation of 524 feet, Hamilton County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Cress during the growing season.

Hamilton County, IL (Zone 6b) Moderate season
197 days
Last Spring Frost April 9
197 growing days
First Fall Frost October 23

Hamilton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (162 days to spare)
Start indoors: Feb 27 Transplant: Apr 3 🍅 Harvest: Apr 17 – May 8
Recommended (50%) ✓ Fits season (162 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: Apr 23 – May 14
Safe Start (90%) ✓ Fits season (172 days to spare)
Start indoors: Mar 16 Transplant: Apr 20 🍅 Harvest: May 4 – May 25

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 Hamilton County

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

Soil pH

Your soil pH (5.8–6.7) overlaps with Cress's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (5.0%) — 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 197-day season

Sow every 1.6 weeks. Last sowing by Oct 02 to harvest before frost.

For a dedicated fall crop, sow by Aug 14.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 355 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 1.5" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 3.8" 0.5" 💧 Light watering
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 5.1" 0" ✅ Rainfall sufficient
Jul 4.3" 4.2" 0.1" 💧 Light watering
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Hamilton 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 ~306 GDD — county provides 3,447 GDD Excellent fit

Cress Planting Timeline — Hamilton County, IL

Cress Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors April 9 Apr 9 – Apr 23
Direct Sow March 26 Mar 26 – Apr 16
Harvest April 23 Apr 23 – May 14
Fall Sowing August 14 Aug 14 – Aug 28

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

14–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

197 days in Hamilton County

Growing Tips for Cress in Hamilton County

Direct sow Cress outdoors after April 09 in Hamilton County when soil has warmed and frost danger has passed.

Your generous 197.0-day season in Hamilton 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 Hamilton County, IL?

Hamilton County is in Zone 6b with an average last frost of April 9. Plan your Cress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hamilton County, IL?

Hamilton County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 23.

🌱

Your Hamilton County Garden Planner — Free

A 24-page printable planner built for Hamilton County (Zone 6b). 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 Hamilton County, IL. 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.