One of the best tools that you have as gardeners to help us determine 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 USDA zone info for Spearfish can be looked at to determine when it's a good idea to plant hemerocallis.

Planting Calendar for Hemerocallis

Frost tolerance for hemerocallis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Hemerocallis are moderately cold tolerant which means that you can start planting them earlier than plants that are more sensitive to the cold.

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

Last Frost Date

On average the last frost is on April 15 in Spearfish. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Spearfish is not always accurate the actual date of last frost changes from year to year. Since half of the time in Spearfish it frosts late in the year after April 15 be ready to protect your hemerocallis in the event of one of those late frosts.

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.