When to Plant Cantaloupe in Multnomah County, OR
Cantaloupe is a sweet, aromatic melon with salmon-colored flesh and a netted rind. It requires a long, warm growing season and is the quintessential summer fruit.
Multnomah County, Oregon 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 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 Cantaloupe 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 Cantaloupe's growing requirements.
Soil pH
Your soil pH (5.8–6.3) overlaps with Cantaloupe's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Multnomah County is excellent for Cantaloupe — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Cantaloupe.
Organic Matter
Organic matter is excellent (4.5%) — Cantaloupe will thrive.
How to Plant Cantaloupe
Succession Planting Cantaloupe
Sow every 8 weeks. Last sowing by Jul 29 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Cantaloupe
Cantaloupe needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.
| Month | Cantaloupe Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 5.8" | 0" | ❄️ Dormant |
| Feb | — | 4.1" | 0" | ❄️ Dormant |
| Mar | — | 3.5" | 0" | ❄️ Dormant |
| Apr | 5.6" | 2.3" | 3.3" | 🚿 Regular watering |
| May | 5.6" | 2.3" | 3.3" | 🚿 Regular watering |
| Jun | 5.6" | 1.3" | 4.3" | 🚿 Regular watering |
| Jul | 5.6" | 0.6" | 5" | 🚿 Regular watering |
| Aug | 5.6" | 0.7" | 4.9" | 🚿 Regular watering |
| Sep | 5.6" | 1.6" | 4" | 🚿 Regular watering |
| Oct | 5.6" | 2.9" | 2.7" | 💧 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.
Cantaloupe 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.
Cantaloupe Planting Timeline — Multnomah County, OR
Cantaloupe Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 5 | May 5 – May 19 |
| Harvest | July 14 | Jul 14 – Aug 18 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.3"/week · 2-3 times/week
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
196 days in Multnomah County
Growing Tips for Cantaloupe in Multnomah County
Direct sow Cantaloupe outdoors after April 14 in Multnomah County when soil has warmed and frost danger has passed.
Common pests for Cantaloupe in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 3-4 weeks early or direct sow on warm mounds. Reduce watering as fruits ripen. Harvest when stem slips easily from the fruit with gentle pressure.
Companion Planting
Good Companions
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Cantaloupe in Other Locations
Frequently Asked Questions
When should I plant Cantaloupe in Multnomah County, OR?
Multnomah County is in Zone 8b with an average last frost of April 14. Plan your Cantaloupe 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 8b. The average last spring frost is April 14 and first fall frost is October 27.
Plan Your Garden with Confidence
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