The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Spearfish can be used to figure out when it's a good idea to plant lupine.

Planting Calendar for Lupine

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

Lupine are one of those plants that can tolerate a little bit of cold weather which means that you can get them planted earlier than plants that are more sensitive to the cold.

The earliest that you can plant lupine 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 lupine and expect a good harvest is probably September. You probably don't want to wait any later than that or else your lupine may not have a chance to fully mature. If you are starting your lupine indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Spearfish. You should expect an average low temperature of -20°F in the coldest months of winter.

Remember that USDA zone info for Spearfish is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Spearfish there is a last frost after April 15 so make sure that you are prepared to cover your lupine 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.