When to Plant Watercress in Grayson County, TX
May in Grayson County, Texas — your action list
A quick May briefing for Grayson County, Texas gardeners — what's urgent, what's next, and what can wait.
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Collect watercress at their peak
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
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.
Grayson County, Texas is in USDA Zone 8a. The average last spring frost is March 14 and the first fall frost is November 18, giving you a growing season of approximately 249 days.
At an elevation of 248 feet, Grayson County receives approximately 71.2 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Watercress during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watercress root diseases.
Grayson County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.3
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 Grayson County
How your county's soil matches Watercress's growing requirements.
Soil pH
Your soil pH (6.6–7.3) is within Watercress's preferred range (6.5–7.5).
Soil Texture
The loam soil in Grayson County is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.1%). 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 19 to harvest before frost.
For a dedicated fall crop, sow by Sep 09.
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 | — | 1.9" | 0" | ❄️ Dormant |
| Feb | — | 2.2" | 0" | ❄️ Dormant |
| Mar | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Apr | 6.5" | 8.5" | 0" | ✅ Rainfall sufficient |
| May | 6.5" | 11.3" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 12.4" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 9.3" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 7.7" | 0" | ✅ Rainfall sufficient |
| Sep | 6.5" | 6.2" | 0.3" | 💧 Light watering |
| Oct | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Nov | 6.5" | 2.1" | 4.4" | 🚿 Regular watering |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Grayson 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 — Grayson County, TX
Watercress Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 7 | Feb 7 – Feb 21 |
| Transplant Outdoors | March 14 | Mar 14 – Mar 28 |
| Direct Sow | February 28 | Feb 28 – Mar 21 |
| Harvest | April 25 | Apr 25 – May 30 |
| Fall Sowing | September 9 | Sep 9 – Sep 23 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1.5"/week · Only during dry spells
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 8a
📆 Growing Season
249 days in Grayson County
Growing Tips for Watercress in Grayson County
Direct sow Watercress outdoors after March 14 in Grayson County when soil has warmed and frost danger has passed.
Your generous 249.0-day season in Grayson 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 Grayson County, TX?
Grayson County is in Zone 8a with an average last frost of March 14. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.
What planting zone is Grayson County, TX?
Grayson County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 14 and first fall frost is November 18.
Your Grayson County Garden Planner — Free
A 24-page printable planner built for Grayson County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.