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 Billings you can estimate when it's the best time to plant angelonia by checking out the USDA zone info.

Planting Calendar for Angelonia

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

Angelonia do ok in very little cold which means that you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant angelonia in Billings 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 angelonia and expect a good harvest is probably August. Any later than that and your angelonia may not have a chance to fully mature. Starting your angelonia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Billings is not always accurate the actual date of last frost changes from year to year. Half of the time in Billings it frosts late in the year after May 15 so make sure that you are ready to cover your angelonia in the event of a surprise late frost.

USDA Zone Info for Billings

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 Billings

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