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.

The first chance to plant cucumbers in Seattle should be estimated by using the USDA zone info.

Planting Calendar for Cucumbers

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

It's probably not a good idea to plant cucumbers until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant cucumbers 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 cucumbers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cucumbers may not have a chance to fully mature. You can get started a few weeks earlier by starting your cucumbers indoors.

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 the actual date of last frost is just an average because it is based on the USDA zone info for Seattle and it can change quite a bit from year to year. Half of the time in Seattle there is a last frost after March 15 so always be ready to cover your cucumbers if you have a surprise 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.