One of the first steps you take when you are determining 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.

You will be able to determine when you can plant flower-of-an-hour by using the USDA zone info for Ann Arbor.

Planting Calendar for Flower-of-an-Hour

Frost tolerance for flower-of-an-hour:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Flower-of-an-Hour are barely cold tolerant which means that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant flower-of-an-hour in Ann Arbor 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 flower-of-an-hour and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to really do well. Starting your flower-of-an-hour indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Ann Arbor. You can expect an average low temperature of -10°F in the coldest months of winter.

Remember that USDA zone info for Ann Arbor is just an average and the actual date of last frost changes from year to year. Since half of the time in Ann Arbor you get a frost after April 15 be ready to cover your flower-of-an-hour if you have a late frost.

USDA Zone Info for Ann Arbor

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 Ann Arbor

You may be interested in your other planting guides for Ann Arbor.