One of the first steps you take when you are figuring out your gardening schedule is find your 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.

One way of figuring out when to plant zinnia is to check out the USDA zone info for Sioux Falls.

Planting Calendar for Zinnia

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

You should not plant zinnia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant zinnia in Sioux Falls 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. You probably don't want to wait any later than that or else your zinnia may not have a chance to grow to maturity. Starting your zinnia indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Sioux Falls the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Sioux Falls is not always accurate and the actual date of last frost is different every year. Half of the time in Sioux Falls last frost occurs after May 15 so always be ready to cover your zinnia in the event of a surprise late frost.

USDA Zone Info for Sioux Falls

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 Sioux Falls

You may be interested in your other planting guides for Sioux Falls.