The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to figure out when it's a good idea to plant thyme by using the USDA zone info for Billings.

Planting Calendar for Thyme

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

Thyme are one of those plants that can tolerate quite a bit of cold weather which means that you can plant them a quite a bit earlier than other plants that might not handle the cold.

The earliest that you can plant thyme in Billings 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 thyme and expect a good harvest is probably August. If you wait any later than that and your thyme may not have a chance to grow to maturity. If you are starting your thyme indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Billings the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Billings and it can change quite a bit from year to year. Half of the time in Billings you get a frost after May 15 so just be sure to be ready to cover your thyme if you have one of those late frosts.

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.