One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Waterloo you can figure out when it's the best time to plant bee balm by checking out the USDA zone info.

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.

Bee Balm are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant bee balm in Waterloo 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. Any later than that and your bee balm may not have a chance to really do well. If you are starting your bee balm indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Waterloo the average date of last frost happens on April 15. You can expect an average low temperature of -10°F in the coldest months of winter.

Remember that USDA zone info for Waterloo is not always accurate and the actual date of last frost changes from year to year. Half of the time in Waterloo last frost occurs after April 15 so be sure to be ready to cover your bee balm if you have a surprise late frost.

USDA Zone Info for Waterloo

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Waterloo

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