Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Elk River you can figure out when it's the best time to plant borage by using the USDA zone info.

Planting Calendar for Borage

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

Since borage are one of those plants that can tolerate a little bit of cold weather you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant borage in Elk River is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant borage and expect a good harvest is probably August. Any later than that and your borage may not have a chance to grow to maturity. If you are starting your borage indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Elk River the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Elk River and it will vary from year to year. Since half of the time in Elk River last frost occurs after May 15 be ready to protect your borage in the event of one of those late frosts.

USDA Zone Info for Elk River

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Elk River

You may be interested in your other planting guides for Elk River.