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.

The USDA zone info for Bozeman should be used to determine when it's possible to plant saxifraga.

Planting Calendar for Saxifraga

Frost tolerance for saxifraga:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since saxifraga do ok in moderate cold you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant saxifraga in Bozeman is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant saxifraga and expect a good harvest is probably August. Any later than that and your saxifraga may not have a chance to grow to maturity. Starting your saxifraga indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Bozeman the average date of last frost happens on May 15. It might get as low as -25°F during the coldest months of winter.

Since the USDA zone info for Bozeman may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Bozeman there is a last frost after May 15 so be sure to be ready to cover your saxifraga if you have 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.