One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of determining when it's possible to plant alternanthera is to look at the USDA zone info for Rapid City.

Planting Calendar for Alternanthera

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

It's probably a bad idea to plant alternanthera until after the last frost because they require warm weather.

The earliest that you can plant alternanthera 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 alternanthera and expect a good harvest is probably August. Any later than that and your alternanthera may not have a chance to really do well. You can get started a little bit earlier by starting your alternanthera indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Rapid City. You should expect an average low temperature of -20°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Rapid City and it will vary from year to year. Since half of the time in Rapid City you get surprised by a frost after April 15 be ready to protect your alternanthera 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.