When Do You Plant Pumpkins In Oregon

If you want to grow your own jack-o’-lanterns or pie pumpkins, timing is everything. Knowing exactly when do you plant pumpkins in Oregon is the first step to a successful harvest. Oregon’s growing season varies dramatically from the coast to the high desert, so getting your planting date right makes all the difference.

This guide will walk you through the best dates, varieties, and care tips for pumpkins across the state. Let’s get your patch started.

The simple answer is: plant pumpkins after the last spring frost when the soil has warmed up. For most of Oregon, this means late May through mid-June. Pumpkins are tender and hate cold soil; planting too early is a common mistake.

Here’s a more detailed regional breakdown:

Willamette Valley & Portland Metro: Aim for late May to June 10. The last frost is typically mid-May, but waiting ensures warm soil.
Southern Oregon (Medford, Ashland): You can often plant a bit earlier, from mid-May onward, thanks to a longer, warmer season.
Central & Eastern Oregon (Bend, Ontario): Wait until early to mid-June. Frost risk persists longer, and the soil takes time to warm.
Oregon Coast (Astoria, Newport): The cool, maritime climate means a shorter season. Start seeds indoors in early May and transplant in early June. Choose smaller, faster-maturing varieties.

Understanding Your Local Frost Dates

Your average last frost date is the key calendar marker. You can find this through your local OSU Extension office. Pumpkins need a long, warm growing period—usually 75 to 120 days from planting to harvest.

Count backward from your first fall frost date. For example, if your first frost is around October 15 and you choose a 100-day pumpkin, you need to plant by early July at the latest. Earlier is generally better.

Starting Seeds Indoors vs. Direct Sowing

You have two main options for getting your pumpkins going. Each has it’s pros and cons.

Starting Pumpkin Seeds Indoors

This method gives you a head start, especially in cooler regions. Start seeds indoors about 2-4 weeks before your planned outdoor transplant date.

Use 3-4 inch biodegradable pots to avoid disturbing roots.
Plant seeds 1 inch deep.
Keep soil warm (75-85°F) for best germination.
Provide plenty of light on a sunny windowsill or under grow lights.
Harden off seedlings for a week before transplanting.

Direct Sowing in the Garden

This is the easiest method if your season is long enough. Pumpkins prefer not to have their roots disturbed. Wait until soil temperature is consistently above 70°F.

Create small hills or mounds of soil about 6 inches high and 3 feet wide. This improves drainage and warms the soil faster.
Space hills 4-8 feet apart, depending on the vining habit of your variety.
Plant 4-5 seeds per hill, about 1 inch deep.
Once seedlings have two true leaves, thin to the 2-3 strongest plants per hill.

Choosing the Right Pumpkin Variety for Oregon

Selecting a variety that matures within your region’s growing season is crucial. Here are some excellent choices for Oregon gardens.

For Pie & Cooking: ‘Sugar Pie’ (100 days), ‘Winter Luxury’ (105 days). These have sweet, fine-grained flesh.
For Jack-o’-Lanterns: ‘Howden’ (115 days), ‘Autumn Gold’ (90 days). They have strong handles and good form.
For Giant Pumpkins: ‘Atlantic Giant’ (120+ days). Only attempt this if you have a very long, warm season and lots of space.
For Short Seasons: ‘Jack Be Little’ (90 days), ‘Baby Pam’ (95 days). Perfect for coastal or late-started gardens.

Preparing Your Oregon Pumpkin Patch

Pumpkins are heavy feeders and need lots of space and sun. A little prep work goes a long way.

Site and Soil Requirements

Choose the sunniest spot in your yard—at least 6-8 hours of direct sun. The soil should be rich and well-draining. Oregon’s heavy winter rains mean drainage is key.

Work in several inches of compost or well-rotted manure before planting. Aim for a soil pH between 6.0 and 6.8. A soil test from OSU Extension can provide specific amendment advice.

Watering and Fertilizing Schedule

Consistent watering is vital, especially during fruit set. Water deeply at the base of the plants, not on the leaves, to help prevent disease. About 1-2 inches per week is a good goal.

Use a balanced fertilizer at planting. When vines start to run, switch to a lower-nitrogen, higher-phosphorus fertilizer to encourage flowering and fruiting. Too much nitrogen late in the season leads to all vines and no pumpkins.

Common Pests and Problems in Oregon

Stay vigilant for these typical issues. Catching them early makes management easier.

Squash Bugs: Hand-pick adults and egg clusters from the undersides of leaves. Use row covers early in the season.
Powdery Mildew: This white fungus thrives in Oregon’s late-summer humidity. Plant resistant varieties, ensure good air circulation, and avoid overhead watering.
Cucumber Beetles: They spread bacterial wilt. Use row covers or apply kaolin clay.
Poor Pollination: If small fruits turn yellow and die, the flowers might not have been pollinated. You can hand-pollinate female flowers (which have a tiny fruit at the base) using a male flower.

Knowing When to Harvest Your Pumpkins

Your pumpkins are ready when they have reached their full color and the rind is hard. You shouldn’t be able to pierce it easily with your fingernail. The vine will often start to die back, and the stem will begin to dry and cork over.

Always cut the pumpkin from the vine with a sharp knife or pruners, leaving a 3-4 inch stem attached. This handle helps prevent rot and looks nicer. Handle them gently to avoid bruises.

If a hard frost is forcasted before your pumpkins are fully mature, you can harvest them and they may still ripen some off the vine, but flavor and storage life won’t be as good.

Curing and Storing Your Oregon Harvest

For storage pumpkins (not immediate carving), cure them in a warm, dry place like a greenhouse or sunny porch for about 10 days. This toughens the skin and heals minor cuts.

After curing, store them in a cool (50-55°F), dry place with good air circulation. Properly cured and stored pumpkins can last for several months, often through the winter.

FAQ: Planting Pumpkins in Oregon

Can I plant pumpkins in July in Oregon?

It depends on your first fall frost date and the variety. In western valleys, planting very fast-maturing (under 90-day) varieties by early July might work. In eastern Oregon, it’s likely too late. Always check the “days to maturity” on your seed packet.

What is the best month to plant pumpkins in Oregon?

For most of the state, June is the safest and best month to plant pumpkins directly outdoors. This gives them the warm soil they need and enough time to mature before fall rains and frost.

How long does it take to grow pumpkins in Oregon?

Most pumpkin varieties need between 90 and 120 warm days from planting to harvest. Your local microclimate and the specific summer weather each year will effect the exact timing.

Can I grow pumpkins in containers on the Oregon coast?

Yes! Choose a compact or bush variety and a very large container (at least 20 gallons). Ensure it has excellent drainage and is placed in the sunniest, most sheltered spot you have. Container plants often need more frequent watering and feeding.

Growing pumpkins in Oregon is a rewarding endevor. By paying close attention to your local planting window, choosing the right variety, and providing consistent care, you’ll be well on your way to a fantastic autumn harvest. Get your seeds ready, watch the weather, and prepare for some vine-taming fun.