When to Plant Watercress in LaSalle Parish, LA
Top priorities for LaSalle Parish, Louisiana gardeners in May
Your LaSalle Parish, Louisiana garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
-
Pick watercress
If you can't use it all right away, check the food-preservation section of your planner.
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.
LaSalle Parish, Louisiana is in USDA Zone 8b. The average last spring frost is March 2 and the first fall frost is November 19, giving you a growing season of approximately 262 days.
At an elevation of 262 feet, LaSalle Parish receives approximately 52.2 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Watercress may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watercress root diseases.
LaSalle Parish Soil Profile
Soil Type
Loam
Soil pH
6.2-7.2
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 LaSalle Parish
How your county's soil matches Watercress's growing requirements.
Soil pH
Your soil pH (6.2–7.2) overlaps with Watercress's range (6.5–7.5), though not a perfect match.
Soil Texture
The loam soil in LaSalle Parish is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). 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 20 to harvest before frost.
For a dedicated fall crop, sow by Sep 10.
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 | — | 4.6" | 0" | ❄️ Dormant |
| Feb | — | 4.3" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4.8" | 1.7" | 💧 Light watering |
| Apr | 6.5" | 4.4" | 2.1" | 💧 Light watering |
| May | 6.5" | 3.9" | 2.6" | 💧 Light watering |
| Jun | 6.5" | 4" | 2.5" | 💧 Light watering |
| Jul | 6.5" | 5.8" | 0.7" | 💧 Light watering |
| Aug | 6.5" | 5.3" | 1.2" | 💧 Light watering |
| Sep | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Oct | 6.5" | 3.5" | 3" | 💧 Light watering |
| Nov | 6.5" | 3.6" | 2.9" | 💧 Light watering |
| Dec | — | 3.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in LaSalle Parish). 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 — LaSalle Parish, LA
Watercress Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 26 | Jan 26 – Feb 9 |
| Transplant Outdoors | March 2 | Mar 2 – Mar 16 |
| Direct Sow | February 16 | Feb 16 – Mar 9 |
| Harvest | April 13 | Apr 13 – May 18 |
| Fall Sowing | September 10 | Sep 10 – Sep 24 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| 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 · 1-2 times/week
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
262 days in LaSalle Parish
Growing Tips for Watercress in LaSalle Parish
Direct sow Watercress outdoors after March 02 in LaSalle Parish when soil has warmed and frost danger has passed.
Your generous 262.0-day season in LaSalle Parish 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 LaSalle Parish, LA?
LaSalle Parish is in Zone 8b with an average last frost of March 2. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.
What planting zone is LaSalle Parish, LA?
LaSalle Parish, Louisiana is in USDA Hardiness Zone 8b. The average last spring frost is March 2 and first fall frost is November 19.
Your LaSalle Parish Garden Planner — Free
A 24-page printable planner built for LaSalle Parish (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.