Before planting it is a good idea to find your USDA Zone info to estimate 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.

You can determine when it's possible to plant larkspur in Bozeman by using the USDA zone info.

Planting Calendar for Larkspur

Frost tolerance for larkspur:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

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

The earliest that you can plant larkspur in Bozeman 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 larkspur and expect a good harvest is probably August. Any later than that and your larkspur may not have a chance to fully mature. If you are starting your larkspur indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Bozeman. You should expect an average low temperature of -25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Bozeman may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Bozeman there is a last frost after May 15 be ready to protect your larkspur in the event of one of those late frosts.

USDA Zone Info for Bozeman

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 Bozeman

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