When to Plant Watercress in Jefferson County, KS
This month in Jefferson County, Kansas
May is a pivotal month for Jefferson County, Kansas gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Indoor seed-starting week for watercress
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
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Collect watercress at their peak
If you can't use it all right away, check the food-preservation section of your planner.
Get ahead of June
- 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.
Jefferson County, Kansas is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 24, giving you a growing season of approximately 193 days.
At an elevation of 559 feet, Jefferson County receives approximately 23.8 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Watercress during the growing season.
Jefferson County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.6
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 Jefferson County
How your county's soil matches Watercress's growing requirements.
Soil pH
Your soil pH (6.7–7.6) overlaps with Watercress's range (6.5–7.5), though not a perfect match.
Soil Texture
The loam soil in Jefferson County is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.3%). Annual compost additions will help Watercress.
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 25 to harvest before frost.
For a dedicated fall crop, sow by Aug 15.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 0.7" | 0" | ❄️ Dormant |
| Mar | — | 1.4" | 0" | ❄️ Dormant |
| Apr | 6.5" | 2.5" | 4" | 🚿 Regular watering |
| May | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| Jun | 6.5" | 3.5" | 3" | 💧 Light watering |
| Jul | 6.5" | 3.5" | 3" | 💧 Light watering |
| Aug | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| Sep | 6.5" | 2.5" | 4" | 🚿 Regular watering |
| Oct | 6.5" | 1.4" | 5.1" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 0.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Jefferson 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 — Jefferson County, KS
Watercress Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 10 | Mar 10 – Mar 24 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | March 31 | Mar 31 – Apr 21 |
| Harvest | May 26 | May 26 – Jun 30 |
| Fall Sowing | August 15 | Aug 15 – Aug 29 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| 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 6b
📆 Growing Season
193 days in Jefferson County
Growing Tips for Watercress in Jefferson County
Direct sow Watercress outdoors after April 14 in Jefferson County when soil has warmed and frost danger has passed.
Your generous 193.0-day season in Jefferson 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.
Jefferson County receives only 24" of rain annually. Watercress needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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 Jefferson County, KS?
Jefferson County is in Zone 6b with an average last frost of April 14. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, KS?
Jefferson County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 24.
Your Jefferson County Garden Planner — Free
A 24-page printable planner built for Jefferson 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.