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.

In La Crosse you can determine when it's a good idea to plant zinnia by reviewing 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.

Zinnia require warm weather which tells us that it's important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant zinnia in La Crosse 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. 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 few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in La Crosse. In the coldest months of winter you can expect an average low temperature of -25°F.

Keep in mind that USDA zone info for La Crosse may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in La Crosse it frosts late in the year after May 15 be ready to cover your zinnia in the event of one of those late frosts.

USDA Zone Info for La Crosse

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 La Crosse

You may be interested in your other planting guides for La Crosse.