Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Portland you will be able to determine when it's possible to plant bower vine.

Planting Calendar for Bower Vine

Frost tolerance for bower vine:	Not tolerant of frost.
When to plant:	After the last frost.

It's not a good idea to plant bower vine until after the last frost because they do not do well in cold weather.

The earliest that you can plant bower vine in Portland 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 bower vine and expect a good harvest is probably August. If you wait any later than that and your bower vine may not have a chance to fully mature. You can get started a few weeks earlier by starting your bower vine indoors.

Last Frost Date

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

Since the USDA zone info for Portland is just an average the actual date of last frost changes from year to year. Half of the time in Portland there is a last frost after March 15 so make sure that you are ready to protect your bower vine if you have a surprise late frost.

USDA Zone Info for Portland

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 Portland

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