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.

A common way of figuring out when it's possible to plant tritoma is to use the USDA zone info for Zone 1a.

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 tells us that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant tritoma in Zone 1a 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 tritoma and expect a good harvest is probably July. 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 June 15 in Zone 1a. In the coldest months of winter you should expect an average low temperature of -60°F.

Always keep in mind that USDA zone info for Zone 1a is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 1a you get a frost after June 15 be ready to protect your tritoma in the event of one of those late frosts.

USDA Zone Info for Zone 1a

Here is the info for USDA Zone 1a.

Average Date of Last Frost (spring)	June 15
Average Date of First Frost (fall)	July 15
Lowest Expected Low	-60°F
Highest Expected Low	-55°F

This means that on a really cold year, the coldest it will get is -60°F. On most years you should be prepared to experience lows near -55°F.

Plants to Grow in Zone 1a

You may be interested in your other planting guides for Zone 1a.