When to Plant Squash (Summer) in Umatilla County, OR
Summer squash includes zucchini, yellow crookneck, and pattypan varieties that are harvested young and tender. They are prolific producers in warm weather.
Umatilla County, Oregon is in USDA Zone 7a. 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 2,195 feet, Umatilla County receives approximately 14.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Squash (Summer) during the growing season. With low rainfall, drip irrigation is essential for growing Squash (Summer) successfully. Mulch heavily to conserve soil moisture.
Umatilla County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.8
Drainage
Well Drained
Monthly Watering Guide for Squash (Summer)
Squash (Summer) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Squash (Summer) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 1.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| May | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Jun | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Jul | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Aug | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Sep | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Oct | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Umatilla County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Squash (Summer) Planting Timeline — Umatilla County, OR
Squash (Summer) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 26 | Mar 26 – Apr 9 |
| Transplant Outdoors | May 7 | May 7 – May 21 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Harvest | June 25 | Jun 25 – Aug 27 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors 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
Moderate — regular watering
📅 Days to Maturity
45–65 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 7a
📆 Growing Season
180 days in Umatilla County
Growing Tips for Umatilla County
Direct sow after last frost on mounds. Harvest frequently when fruits are 6-8 inches for best texture. Check plants daily as they grow rapidly in summer heat.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Squash (Summer) in Other Locations
Frequently Asked Questions
When should I plant Squash (Summer) in Umatilla County, OR?
Umatilla County is in Zone 7a with an average last frost of April 23. Plan your Squash (Summer) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Umatilla County, OR?
Umatilla County, Oregon is in USDA Hardiness Zone 7a. The average last spring frost is April 23 and first fall frost is October 20.
Your Umatilla County Garden Planner — Free
A 22-page printable planner built for Umatilla County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.