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.

The earliest that you can plant anchusa in Rapid City can be figured out by reviewing the USDA zone info.

Planting Calendar for Anchusa

Frost tolerance for anchusa:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Anchusa can survive in cold weather which means that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant anchusa in Rapid City is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant anchusa and expect a good harvest is probably September. Any later than that and your anchusa may not have a chance to really do well. If you are starting your anchusa indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Rapid City may not be accurate from year to year 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 anchusa 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.