The USDA Zone info is a great tool for gardeners to help us determine 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 possible to determine when it's a good idea to plant tritoma by using the USDA zone info for Havre.

Planting Calendar for Tritoma

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

Tritoma do well in cold which means that you can plant them a quite a bit earlier than more sensitive plants.

The earliest that you can plant tritoma in Havre 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 tritoma and expect a good harvest is probably August. You probably don't want to wait any later than that or else your tritoma may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your tritoma indoors.

Last Frost Date

The average date of last frost is May 15 in Havre. It might get as low as -30°F during the coldest months of winter.

Always keep in mind that USDA zone info for Havre is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Havre you get a frost after May 15 be ready to cover your tritoma if you have one of those late frosts.

USDA Zone Info for Havre

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 Havre

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