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 best time to plant coreopsis in Spearfish should be determined by using the USDA zone info.

Planting Calendar for Coreopsis

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

Coreopsis are one of those plants that can tolerate a little bit of cold weather which tells us that you can start planting them earlier than more sensitive plants.

The earliest that you can plant coreopsis 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 coreopsis and expect a good harvest is probably September. If you wait any later than that and your coreopsis may not have a chance to grow to maturity. You can get started a little bit earlier by starting your coreopsis indoors.

Last Frost Date

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

Just be sure to remember that USDA zone info for Spearfish is an average and the actual date of last frost will vary from year to year. Half of the time in Spearfish it frosts late in the year after April 15 so make sure that you are prepared to cover your coreopsis 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.