One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant borage in Helena should be estimated by reviewing 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.

Borage can survive in a little bit of cold which means that you can plant them just a bit earlier in the year than other frost tender plants.

The earliest that you can plant borage in Helena 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. If you wait any later than that and your borage may not have a chance to grow to maturity. Starting your borage indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Helena. It might get as low as 10°F during the coldest months of winter.

Since the USDA zone info for Helena is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Helena there is a last frost after March 15 be ready to cover your borage if you have a late frost.

USDA Zone Info for Helena

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Helena

You may be interested in your other planting guides for Helena.