Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By referring to the USDA zone info for Seattle you should be able to estimate when it's possible to plant pumpkins.

Planting Calendar for Pumpkins

Frost tolerance for pumpkins:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Pumpkins do not do well in cold weather which tells us that it is important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant pumpkins in Seattle is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant pumpkins and expect a good harvest is probably August. Any later than that and your pumpkins may not have a chance to fully mature. If you are starting your pumpkins indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Seattle the average date of last frost happens on March 15. You should expect an average low temperature of 15°F in the coldest months of winter.

Remember that USDA zone info for Seattle is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Seattle you get surprised by a frost after March 15 be ready to protect your pumpkins in the event of a late frost.

USDA Zone Info for Seattle

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Seattle

You may be interested in your other planting guides for Seattle.