Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Rapid City can be used to figure out when it's possible to plant begonias.

Planting Calendar for Begonias

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

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

The earliest that you can plant begonias in Rapid 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 begonias and expect a good harvest is probably August. If you wait any later than that and your begonias may not have a chance to fully mature. If you are starting your begonias indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Since the USDA zone info for Rapid City is an average the actual date of last frost changes from year to year. Since half of the time in Rapid City it frosts late in the year after April 15 be ready to protect your begonias if you have a surprise late frost.

USDA Zone Info for Rapid 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 Rapid City

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