One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant dipladenia in Rapid City should be determined by reviewing the USDA zone info.

Planting Calendar for Dipladenia

Frost tolerance for dipladenia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Dipladenia are not cold tolerant which means that it is important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant dipladenia 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 dipladenia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dipladenia may not have a chance to really do well. You can get started a few weeks earlier by starting your dipladenia indoors.

Last Frost Date

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

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Rapid City and it will vary from year to year. Half of the time in Rapid City you get a frost after April 15 so make sure that you are ready to cover your dipladenia in the event of 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.