When to Plant Malabar Spinach in Whatcom County, WA
Malabar spinach is a tropical vine with thick, succulent leaves that taste similar to spinach. Unlike true spinach, it thrives in heat and humidity.
Whatcom County, Washington is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is October 29, giving you a growing season of approximately 206 days.
At an elevation of 386 feet, Whatcom County receives approximately 49 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Malabar Spinach during the growing season.
Whatcom County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.4
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 Whatcom County
How your county's soil matches Malabar Spinach's growing requirements.
Soil pH
Your soil pH (5.2–6.4) is more acidic than Malabar Spinach prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Whatcom County is excellent for Malabar Spinach — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.7%) — Malabar Spinach will thrive.
How to Plant Malabar Spinach
Succession Planting Malabar Spinach
Sow every 6.3 weeks. Last sowing by Aug 20 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Malabar Spinach
Malabar Spinach 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 | Malabar Spinach Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 6.1" | 0" | ❄️ Dormant |
| Feb | — | 6.2" | 0" | ❄️ Dormant |
| Mar | — | 4.3" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3.8" | 2.7" | 💧 Light watering |
| May | 6.5" | 3.1" | 3.4" | 🚿 Regular watering |
| Jun | 6.5" | 2.1" | 4.4" | 🚿 Regular watering |
| Jul | 6.5" | 0.7" | 5.8" | 🚿 Regular watering |
| Aug | 6.5" | 0.9" | 5.6" | 🚿 Regular watering |
| Sep | 6.5" | 2" | 4.5" | 🚿 Regular watering |
| Oct | 6.5" | 4.5" | 2" | 💧 Light watering |
| Nov | — | 7.1" | 0" | ❄️ Dormant |
| Dec | — | 8.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Whatcom County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Malabar Spinach 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.
Malabar Spinach Planting Timeline — Whatcom County, WA
Malabar Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 16 | Feb 16 – Mar 2 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | June 15 | Jun 15 – Jul 13 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
55–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_acidic
🗺️ USDA Zone
Zone 7b
📆 Growing Season
206 days in Whatcom County
Growing Tips for Malabar Spinach in Whatcom County
Direct sow Malabar Spinach outdoors after April 06 in Whatcom County when soil has warmed and frost danger has passed.
General growing tips
Direct sow after last frost or start indoors. Provide a trellis for the vigorous vines. Harvest young leaves regularly; older leaves become mucilaginous when cooked.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Malabar Spinach in Other Locations
Frequently Asked Questions
When should I plant Malabar Spinach in Whatcom County, WA?
Whatcom County is in Zone 7b with an average last frost of April 6. Plan your Malabar Spinach planting based on this frost date — see the calendar above for exact timing.
What planting zone is Whatcom County, WA?
Whatcom County, Washington is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is October 29.
Plan Your Garden with Confidence
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