One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's a good idea to plant tritoma in Lewiston by reviewing the USDA zone info.

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 get them planted much earlier than other frost tender plants.

The earliest that you can plant tritoma in Lewiston is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant tritoma and expect a good harvest is probably September. If you wait 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 little bit earlier.

Last Frost Date

In Lewiston the average date of last frost happens on April 15. You should expect an average low temperature of 5°F in the coldest months of winter.

Always keep in mind that USDA zone info for Lewiston is just an average and the actual date of last frost changes from year to year. Since half of the time in Lewiston it frosts late in the year after April 15 be ready to protect your tritoma in the event of a late frost.

USDA Zone Info for Lewiston

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Lewiston

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