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.

In Tucson you can determine when it's a good idea to plant tithonia by checking out the USDA zone info.

Planting Calendar for Tithonia

Frost tolerance for tithonia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Tithonia require warm weather which means that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant tithonia in Tucson 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 tithonia and expect a good harvest is probably September. Any later than that and your tithonia may not have a chance to really do well. You can get started a few weeks earlier by starting your tithonia indoors.

Last Frost Date

In Tucson the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Keep in mind that USDA zone info for Tucson may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Tucson it frosts late in the year after February 15 so be sure to be ready to protect your tithonia if you have a surprise late frost.

USDA Zone Info for Tucson

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Tucson

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