When to Plant Pawpaw in Multnomah County, OR
May in the garden — Multnomah County, Oregon
May is a pivotal month for Multnomah County, Oregon gardens. Focus on these tasks first and you'll set up the rest of the season for success.
Pawpaw is the largest native fruit tree in North America, producing tropical-tasting custard-like fruits. Young trees prefer shade but fruiting trees need good light.
Multnomah County, Oregon is in USDA Zone 9a. 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 357 feet, Multnomah County receives approximately 35.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Pawpaw to ensure they mature before fall.
Multnomah County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.3
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 Multnomah County
How your county's soil matches Pawpaw's growing requirements.
Soil pH
Your soil pH (5.8–6.3) is within Pawpaw's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Multnomah County is excellent for Pawpaw — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Pawpaw.
Organic Matter
Organic matter is excellent (4.5%) — Pawpaw will thrive.
How to Plant Pawpaw
Plant Water Budget
Monthly Watering Guide for Pawpaw
Pawpaw needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Pawpaw Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.8" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | — | 3.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.3" | 2" | 💧 Light watering |
| May | 4.3" | 2.3" | 2" | 💧 Light watering |
| Jun | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Jul | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Oct | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Nov | — | 6" | 0" | ❄️ Dormant |
| Dec | — | 4.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Multnomah County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Pawpaw 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.
Pawpaw Planting Timeline — Multnomah County, OR
Pawpaw Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 28 | Apr 28 – May 12 |
· 120" apart · Rows 144" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
1095–2555 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 9a
📆 Growing Season
196 days in Multnomah County
Growing Tips for Pawpaw in Multnomah County
Direct sow Pawpaw outdoors after April 14 in Multnomah County when soil has warmed and frost danger has passed.
Your 196.0-day growing season in Multnomah County is tight for Pawpaw (1095.0-2555.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
Plant at least two genetically distinct trees for cross-pollination. Provide shade for young trees. Fruits ripen in fall and have a very short shelf life. Harvest when slightly soft.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Pawpaw in Other Locations
Frequently Asked Questions
When should I plant Pawpaw in Multnomah County, OR?
Multnomah County is in Zone 9a with an average last frost of April 14. Plan your Pawpaw planting based on this frost date — see the calendar above for exact timing.
What planting zone is Multnomah County, OR?
Multnomah County, Oregon is in USDA Hardiness Zone 9a. The average last spring frost is April 14 and first fall frost is October 27.
Your Multnomah County Garden Planner — Free
A 24-page printable planner built for Multnomah County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.