Before planting it is a good idea to find your USDA Zone info to figure out 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.

A way of figuring out when it's a good idea to plant impatiens is to look at the USDA zone info for Winterset.

Planting Calendar for Impatiens

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

Since impatiens do not do well in cold weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant impatiens in Winterset 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. Any later than that and your impatiens may not have a chance to really do well. You can get started a few weeks earlier by starting your impatiens indoors.

Last Frost Date

The average date of last frost is April 15 in Winterset. You should expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Winterset and it will vary from year to year. Half of the time in Winterset last frost occurs after April 15 so make sure that you are prepared to protect your impatiens if you have a surprise late frost.

USDA Zone Info for Winterset

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 Winterset

You may be interested in your other planting guides for Winterset.