The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant flowering maple in Portland can be determined by using the USDA zone info.

Planting Calendar for Flowering Maple

Frost tolerance for flowering maple:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's probably a bad idea to plant flowering maple until after the last frost because they are not cold tolerant.

The earliest that you can plant flowering maple 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 flowering maple and expect a good harvest is probably August. Any later than that and your flowering maple may not have a chance to fully mature. Starting your flowering maple indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Portland. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Portland may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Portland last frost occurs after April 15 be ready to protect your flowering maple if you have 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.