One of the best tools that you have as gardeners to help us determine 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.

You should be able to determine when it's the best time to plant zinnia by referring to the USDA zone info for Wisconsin Rapids.

Planting Calendar for Zinnia

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

Zinnia are not cold tolerant which means that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant zinnia in Wisconsin Rapids is May. However, you really should wait until June 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. If you wait any later than that and your zinnia may not have a chance to grow to maturity. If you are starting your zinnia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Wisconsin Rapids the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Wisconsin Rapids is just an average the actual date of last frost is different every year. Since half of the time in Wisconsin Rapids you get a frost after May 15 be ready to cover your zinnia if you have one of those late frosts.

USDA Zone Info for Wisconsin Rapids

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Wisconsin Rapids

You may be interested in your other planting guides for Wisconsin Rapids.