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 earliest that you can plant armeria in Spearfish should be estimated by checking out the USDA zone info.

Planting Calendar for Armeria

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

Since armeria do well in cold you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant armeria in Spearfish 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 armeria and expect a good harvest is probably September. Any later than that and your armeria may not have a chance to fully mature. You can get started a few weeks earlier by starting your armeria indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Spearfish. It might get as low as -20°F during the coldest months of winter.

Keep in mind that USDA zone info for Spearfish is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Spearfish you get a frost after April 15 be ready to cover your armeria in the event of a late frost.

USDA Zone Info for Spearfish

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 Spearfish

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