The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Portland can be reffered to in order to figure out when it's a good idea to plant bee balm.

Planting Calendar for Bee Balm

Frost tolerance for bee balm:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since bee balm do ok in moderate cold you can plant them just a tiny bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bee balm in Portland is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant bee balm and expect a good harvest is probably August. If you wait any later than that and your bee balm may not have a chance to grow to maturity. Starting your bee balm indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost 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 is an average the actual date of last frost will vary from year to year. Half of the time in Portland last frost occurs after April 15 so make sure that you are ready to protect your bee balm 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.