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

By reviewing the USDA zone info for Umatilla it's a good idea to determine when it's a good idea to plant tritoma.

Planting Calendar for Tritoma

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

Tritoma tend to make it in a bit of cold which means that you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant tritoma in Umatilla 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. You probably don't want to wait any later than that or else your tritoma may not have a chance to fully mature. Starting your tritoma indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Umatilla. It might get as low as 5°F during the coldest months of winter.

It's important to remember that USDA zone info for Umatilla may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Umatilla you get a frost after April 15 so just be sure to be ready to protect your tritoma in the event of a surprise late frost.

USDA Zone Info for Umatilla

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 Umatilla

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