When to Plant Purslane in Spokane County, WA
Purslane is a succulent edible plant rich in omega-3 fatty acids, often considered a weed but increasingly valued as a nutritious green. It has a lemony, peppery flavor.
Spokane County, Washington is in USDA Zone 6a. The average last spring frost is May 11 and the first fall frost is September 27, giving you a growing season of approximately 139 days.
At an elevation of 1,645 feet, Spokane County receives approximately 20.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Purslane during the growing season.
Spokane County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.2
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 Spokane County
How your county's soil matches Purslane's growing requirements.
Soil pH
Your soil pH (5.5–6.2) is within Purslane's preferred range (5.5–7.5).
Soil Texture
The silt loam soil in Spokane County is excellent for Purslane — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.4%) — Purslane will thrive.
How to Plant Purslane
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Purslane
Sow every 4.6 weeks. Last sowing by Jul 29 to harvest before frost.
For a dedicated fall crop, sow by Jul 19.
Plant Water Budget
Monthly Watering Guide for Purslane
Purslane needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Purslane Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.1" | 0" | ❄️ Dormant |
| Feb | — | 2.2" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Jun | 2.2" | 0.8" | 1.4" | 🚿 Regular watering |
| Jul | 2.2" | 0.3" | 1.9" | 🚿 Regular watering |
| Aug | 2.2" | 0.4" | 1.8" | 🚿 Regular watering |
| Sep | 2.2" | 0.7" | 1.5" | 🚿 Regular watering |
| Oct | — | 1.5" | 0" | ❄️ Dormant |
| Nov | — | 3.3" | 0" | ❄️ Dormant |
| Dec | — | 3.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Spokane County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Purslane 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.
Purslane Planting Timeline — Spokane County, WA
Purslane Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 6 | Apr 6 – Apr 20 |
| Transplant Outdoors | May 11 | May 11 – May 25 |
| Direct Sow | April 27 | Apr 27 – May 18 |
| Harvest | June 22 | Jun 22 – Jul 27 |
| Fall Sowing | July 19 | Jul 19 – Aug 2 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 5.5–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 6a
📆 Growing Season
139 days in Spokane County
Growing Tips for Purslane in Spokane County
Direct sow Purslane outdoors after May 11 in Spokane County when soil has warmed and frost danger has passed.
Spokane County receives only 20" of rain annually. Purslane needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow after last frost or allow to self-seed. Purslane thrives in hot, dry conditions. Harvest stem tips regularly. Contains more omega-3 fatty acids than any other leafy green.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Purslane in Other Locations
Frequently Asked Questions
When should I plant Purslane in Spokane County, WA?
Spokane County is in Zone 6a with an average last frost of May 11. Plan your Purslane planting based on this frost date — see the calendar above for exact timing.
What planting zone is Spokane County, WA?
Spokane County, Washington is in USDA Hardiness Zone 6a. The average last spring frost is May 11 and first fall frost is September 27.
Plan Your Garden with Confidence
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