When to Plant Watercress in DeWitt County, IL
Your May planting checklist for DeWitt County, Illinois
A quick May briefing for DeWitt County, Illinois gardeners — what's urgent, what's next, and what can wait.
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Indoor seed-starting week for watercress
A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.
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It's harvest week for watercress
If you can't use it all right away, check the food-preservation section of your planner.
Before June arrives, get these ready
- First harvests: watercress
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.
DeWitt County, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 17, giving you a growing season of approximately 185 days.
At an elevation of 801 feet, DeWitt County receives approximately 31.8 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.
DeWitt County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7
Drainage
Well Drained
Plant Planting Risk Windows
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 DeWitt County
How your county's soil matches Watercress's growing requirements.
Soil pH
Your soil pH (6.1–7.0) overlaps with Watercress's range (6.5–7.5), though not a perfect match.
Soil Texture
The silt loam soil in DeWitt County is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Watercress is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is excellent (5.0%) — Watercress will thrive.
How to Plant Watercress
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Watercress
Sow every 4.6 weeks. Last sowing by Aug 18 to harvest before frost.
For a dedicated fall crop, sow by Aug 08.
Plant Water Budget
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| May | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Jun | 6.5" | 4.3" | 2.2" | 💧 Light watering |
| Jul | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| Aug | 6.5" | 3.6" | 2.9" | 💧 Light watering |
| Sep | 6.5" | 2.7" | 3.8" | 🚿 Regular watering |
| Oct | 6.5" | 2.3" | 4.2" | 🚿 Regular watering |
| Nov | — | 2.1" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in DeWitt 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 Planting Timeline — DeWitt County, IL
Watercress Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 11 | Mar 11 – Mar 25 |
| Transplant Outdoors | April 15 | Apr 15 – Apr 29 |
| Direct Sow | April 1 | Apr 1 – Apr 22 |
| Harvest | May 27 | May 27 – Jul 1 |
| Fall Sowing | August 8 | Aug 8 – Aug 22 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6a
📆 Growing Season
185 days in DeWitt County
Growing Tips for Watercress in DeWitt County
Direct sow Watercress outdoors after April 15 in DeWitt County when soil has warmed and frost danger has passed.
Your generous 185.0-day season in DeWitt County allows multiple plantings of Watercress. Sow every 20.0 days for continuous harvest.
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 →
Watercress in Other Locations
Frequently Asked Questions
When should I plant Watercress in DeWitt County, IL?
DeWitt County is in Zone 6a with an average last frost of April 15. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.
What planting zone is DeWitt County, IL?
DeWitt County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 17.
Your DeWitt County Garden Planner — Free
A 24-page printable planner built for DeWitt 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.