One of the best tools that you have as gardeners to help us estimate 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.

By referring to the USDA zone info for Spearfish you will be able to determine when it's the best time to plant borage.

Planting Calendar for Borage

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

Borage are moderately cold tolerant which means that you can get them planted earlier than other plants that might not handle the cold.

The earliest that you can plant borage 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 borage and expect a good harvest is probably September. You probably don't want to wait any later than that or else your borage may not have a chance to fully mature. You can get started a little bit earlier by starting your borage indoors.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Spearfish and it will vary from year to year. Since half of the time in Spearfish last frost occurs after April 15 be ready to protect your borage 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.