One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 Manitowoc you can estimate when you can plant zinnia by using the USDA zone info.

Planting Calendar for Zinnia

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

It's probably not a good idea to plant zinnia until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant zinnia in Manitowoc 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. You can get started a couple of weeks earlier by starting your zinnia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Manitowoc. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Manitowoc is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Manitowoc it frosts late in the year after April 15 so make sure that you are prepared to protect your zinnia in the event of a surprise late frost.

USDA Zone Info for Manitowoc

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 Manitowoc

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