When to Plant Zinnia in Ann Arbor, MI

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 first chance to plant zinnia in Ann Arbor can be determined by reviewing the USDA zone info.


Planting Calendar for Zinnia

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

Since zinnia require warm weather you must wait until after the last frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant zinnia
Possibly ok, but a risky time to plant zinnia
Probably not a good time to plant zinnia

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

Last Frost Date

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

Just be sure to remember that USDA zone info for Ann Arbor is just an average and the actual date of last frost changes from year to year. Half of the time in Ann Arbor you get a frost after April 15 so make sure that you are ready to protect your zinnia 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.