When to Plant Cucumber in Clark County, WA
This month in Clark County, Washington
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Clark County, Washington.
-
Start cucumber under lights
You're about 25 weeks out from your last frost — the perfect window to get these germinating indoors.
June will be here before you know it — start on
- First harvests: cucumber
Cucumbers are a warm-season vine crop available in slicing and pickling varieties. They are prolific producers when given warmth, moisture, and a trellis to climb.
Clark County, Washington is in USDA Zone 8b. The average last spring frost is April 14 and the first fall frost is October 27, giving you a growing season of approximately 196 days.
At an elevation of 482 feet, Clark County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Cucumber during the growing season.
Clark County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.3
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 Clark County
How your county's soil matches Cucumber's growing requirements.
Soil pH
Your soil pH (5.4–6.3) is more acidic than Cucumber prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Clark County is excellent for Cucumber — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Cucumber is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is excellent (4.8%) — Cucumber will thrive.
How to Plant Cucumber
Succession Planting Cucumber
Sow every 5.7 weeks. Last sowing by Aug 18 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Cucumber
Cucumber 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 | Cucumber Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.4" | 0" | ❄️ Dormant |
| Feb | — | 4.6" | 0" | ❄️ Dormant |
| Mar | — | 4" | 0" | ❄️ Dormant |
| Apr | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| May | 6.5" | 2.5" | 4" | 🚿 Regular watering |
| Jun | 6.5" | 1.7" | 4.8" | 🚿 Regular watering |
| Jul | 6.5" | 0.6" | 5.9" | 🚿 Regular watering |
| Aug | 6.5" | 0.8" | 5.7" | 🚿 Regular watering |
| Sep | 6.5" | 1.5" | 5" | 🚿 Regular watering |
| Oct | 6.5" | 3.1" | 3.4" | 🚿 Regular watering |
| Nov | — | 5.9" | 0" | ❄️ Dormant |
| Dec | — | 7.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Clark County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cucumber 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.
Cucumber Planting Timeline — Clark County, WA
Cucumber Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
| Direct Sow | April 21 | Apr 21 – May 12 |
| Harvest | June 23 | Jun 23 – Aug 18 |
Plant 0.5" deep · 24" apart · Rows 48" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 8b
📆 Growing Season
196 days in Clark County
Growing Tips for Cucumber in Clark County
Direct sow Cucumber outdoors after April 14 in Clark County when soil has warmed and frost danger has passed.
Common pests for Cucumber in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost or start indoors 3 weeks early. Provide a trellis for vining types to save space and improve air circulation. Harvest frequently to encourage production.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cucumber in Other Locations
Frequently Asked Questions
When should I plant Cucumber in Clark County, WA?
Clark County is in Zone 8b with an average last frost of April 14. Plan your Cucumber planting based on this frost date — see the calendar above for exact timing.
What planting zone is Clark County, WA?
Clark County, Washington is in USDA Hardiness Zone 8b. The average last spring frost is April 14 and first fall frost is October 27.
Your Clark County Garden Planner — Free
A 24-page printable planner built for Clark County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.