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 earliest that you can plant salpiglossis in Miles City can be determined by reviewing the USDA zone info.

Planting Calendar for Salpiglossis

Frost tolerance for salpiglossis:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Salpiglossis are not cold tolerant which tells us that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant salpiglossis in Miles City is May. However, you really should wait until June if you don't want to take any chances.

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

Last Frost Date

In Miles City the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Miles City is an average and the actual date of last frost changes from year to year. Half of the time in Miles City there is a last frost after May 15 so always be ready to cover your salpiglossis in the event of a late frost.

USDA Zone Info for Miles City

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Miles City

You may be interested in your other planting guides for Miles City.