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

One way of getting a good idea when to plant morning glory is to consult the USDA zone info for Portland.

Planting Calendar for Morning Glory

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

You should not plant morning glory until after the last frost because they do not do well in cold weather.

The earliest that you can plant morning glory 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 morning glory and expect a good harvest is probably August. You probably don't want to wait any later than that or else your morning glory may not have a chance to fully mature. Starting your morning glory indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Portland the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Portland and it is different every year. Since half of the time in Portland you get a frost after April 15 be ready to cover your morning glory in the event of a surprise late frost.

USDA Zone Info for Portland

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°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 -10°F.

Plants to Grow in Portland

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