When to Plant Watercress in Robeson County, NC
May in the garden — Robeson County, North Carolina
Each item below is timed to Robeson County, North Carolina's frost dates and soil temperatures. Skip nothing, stress about nothing.
-
Harvest watercress as they ripen
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
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.
Robeson County, North Carolina is in USDA Zone 8b. The average last spring frost is March 24 and the first fall frost is November 6, giving you a growing season of approximately 227 days.
At an elevation of 887 feet, Robeson County receives approximately 49.7 inches of rainfall annually with predominantly clay loam soil. Summer highs average 97°F, so Watercress may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Watercress, but amend with compost to improve drainage and prevent root rot.
Robeson County Soil Profile
Soil Type
Clay Loam
Soil pH
5.3-6.2
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 Robeson County
How your county's soil matches Watercress's growing requirements.
Soil pH
Your soil pH (5.3–6.2) is more acidic than Watercress prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The clay loam soil in Robeson County is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). 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 Sep 07 to harvest before frost.
For a dedicated fall crop, sow by Aug 28.
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 | — | 3.7" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4.9" | 1.6" | 💧 Light watering |
| Apr | 6.5" | 3.8" | 2.7" | 💧 Light watering |
| May | 6.5" | 3.6" | 2.9" | 💧 Light watering |
| Jun | 6.5" | 4.9" | 1.6" | 💧 Light watering |
| Jul | 6.5" | 5" | 1.5" | 💧 Light watering |
| Aug | 6.5" | 5.3" | 1.2" | 💧 Light watering |
| Sep | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Oct | 6.5" | 2.9" | 3.6" | 🚿 Regular watering |
| Nov | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| Dec | — | 4.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Robeson 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 — Robeson County, NC
Watercress Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 17 | Feb 17 – Mar 3 |
| Transplant Outdoors | March 24 | Mar 24 – Apr 7 |
| Direct Sow | March 10 | Mar 10 – Mar 31 |
| Harvest | May 5 | May 5 – Jun 9 |
| Fall Sowing | August 28 | Aug 28 – Sep 11 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors |
| May | Harvest |
| June | Harvest |
| July | — |
| August | Fall Sowing |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
227 days in Robeson County
Growing Tips for Watercress in Robeson County
Direct sow Watercress outdoors after March 24 in Robeson County when soil has warmed and frost danger has passed.
With Robeson County's clay soil (31% clay), work in 3-4 inches of compost before planting Watercress. Avoid tilling when soil is wet to prevent compaction.
With summer highs reaching 97°F in Robeson County, provide afternoon shade for Watercress and water deeply in the morning.
Your generous 227.0-day season in Robeson 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 Robeson County, NC?
Robeson County is in Zone 8b with an average last frost of March 24. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.
What planting zone is Robeson County, NC?
Robeson County, North Carolina is in USDA Hardiness Zone 8b. The average last spring frost is March 24 and first fall frost is November 6.
Your Robeson County Garden Planner — Free
A 24-page printable planner built for Robeson County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.