Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when it's the best time to plant tritoma is to use the USDA zone info for Williston.

Planting Calendar for Tritoma

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

Tritoma are one of those plants that can tolerate quite a bit of cold weather which tells us that you can plant them much earlier than other frost tender plants.

The earliest that you can plant tritoma in Williston 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. Any later than that and your tritoma may not have a chance to fully mature. Starting your tritoma indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Williston. You should expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Williston is just an average the actual date of last frost will vary from year to year. Since half of the time in Williston you get surprised by a frost after May 15 be ready to cover your tritoma in the event of one of those late frosts.

USDA Zone Info for Williston

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 Williston

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