When to Plant Watercress in Wrangell City and Borough, AK
Your May game plan for Wrangell City and Borough, Alaska
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
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Fire up the seed-starting tray: watercress
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
June will be here before you know it — start on
- 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.
Wrangell City and Borough, Alaska is in USDA Zone 7b. The average last spring frost is April 23 and the first fall frost is October 20, giving you a growing season of approximately 180 days.
At an elevation of 1,533 feet, Wrangell City and Borough receives approximately 35.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 59°F, so choose short-season varieties of Watercress to ensure they mature before fall.
Wrangell City and Borough Soil Profile
Soil Type
Silt Loam
Soil pH
5.1-6.5
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 Wrangell City and Borough
How your county's soil matches Watercress's growing requirements.
Soil pH
Your soil pH (5.1–6.5) is more acidic than Watercress prefers (6.5–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Wrangell City and Borough is excellent for Watercress — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Watercress.
Organic Matter
Organic matter is excellent (6.1%) — 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 21 to harvest before frost.
For a dedicated fall crop, sow by Aug 11.
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 | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | 6.5" | 1.1" | 5.4" | 🚿 Regular watering |
| May | 6.5" | 1.4" | 5.1" | 🚿 Regular watering |
| Jun | 6.5" | 2.9" | 3.6" | 🚿 Regular watering |
| Jul | 6.5" | 4.4" | 2.1" | 💧 Light watering |
| Aug | 6.5" | 6.2" | 0.3" | 💧 Light watering |
| Sep | 6.5" | 5.4" | 1.1" | 💧 Light watering |
| Oct | 6.5" | 4.8" | 1.7" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Wrangell City and Borough). 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 — Wrangell City and Borough, AK
Watercress Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Harvest | June 4 | Jun 4 – Jul 9 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| 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: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
180 days in Wrangell City and Borough
Growing Tips for Watercress in Wrangell City and Borough
Direct sow Watercress outdoors after April 23 in Wrangell City and Borough when soil has warmed and frost danger has passed.
Your generous 180.0-day season in Wrangell City and Borough 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 Wrangell City and Borough, AK?
Wrangell City and Borough is in Zone 7b with an average last frost of April 23. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.
What planting zone is Wrangell City and Borough, AK?
Wrangell City and Borough, Alaska is in USDA Hardiness Zone 7b. The average last spring frost is April 23 and first fall frost is October 20.
Your Wrangell City and Borough Garden Planner — Free
A 24-page printable planner built for Wrangell City and Borough (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.