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.

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

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 a bit of cold which means that you can plant them a lot earlier in the year than more sensitive plants.

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

The last month that you can plant tritoma and expect a good harvest is probably October. If you wait any later than that and your tritoma may not have a chance to grow to maturity. If you are starting your tritoma indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on February 15 in Sonora. It might get as low as 20°F during the coldest months of winter.

Always keep in mind that USDA zone info for Sonora may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Sonora last frost occurs after February 15 so make sure that you are prepared to protect your tritoma if you have a surprise late frost.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sonora

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