One of the best tools that you have as gardeners to help us estimate 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 South Sioux City you can estimate when to plant impatiens by looking at the USDA zone info.

Planting Calendar for Impatiens

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

It's a bad idea to plant impatiens until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant impatiens in South Sioux City 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 impatiens and expect a good harvest is probably August. If you wait any later than that and your impatiens may not have a chance to really do well. If you are starting your impatiens indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In South Sioux City the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Always keep in mind that USDA zone info for South Sioux City is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in South Sioux City you get a frost after April 15 so always be ready to cover your impatiens if you have a surprise late frost.

USDA Zone Info for South Sioux City

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in South Sioux City

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