Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By using the USDA zone info for Ann Arbor you should be able to estimate when you can plant mimulus.

Planting Calendar for Mimulus

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

Mimulus are not cold tolerant which tells us that it is necessary to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant mimulus in Ann Arbor 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 mimulus and expect a good harvest is probably August. If you wait any later than that and your mimulus may not have a chance to fully mature. Starting your mimulus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Ann Arbor is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Ann Arbor it frosts late in the year after April 15 be ready to protect your mimulus in the event of a surprise 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.