The USDA Zone info is a great tool for gardeners to help us estimate 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.

It's a good idea to figure out when it's a good idea to plant zinnia by using the USDA zone info for South Milwaukee.

Planting Calendar for Zinnia

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

Zinnia do not do well in cold weather which tells us that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant zinnia in South Milwaukee 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. You probably don't want to wait any later than that or else your zinnia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your zinnia indoors.

Last Frost Date

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

Since the USDA zone info for South Milwaukee is not always accurate the actual date of last frost is different every year. Half of the time in South Milwaukee it frosts late in the year after April 15 so make sure that you are ready to cover your zinnia in the event of a surprise late frost.

USDA Zone Info for South Milwaukee

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 South Milwaukee

You may be interested in your other planting guides for South Milwaukee.