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 Zone 9b you can determine when it's a good idea to plant tithonia by looking at the USDA zone info.

Planting Calendar for Tithonia

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

Tithonia are not cold tolerant which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant tithonia in Zone 9b 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. You probably don't want to wait any later than that or else your tithonia may not have a chance to really do well. Starting your tithonia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Zone 9b the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Zone 9b may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Zone 9b last frost occurs after February 15 be ready to protect your tithonia if you have a late frost.

USDA Zone Info for Zone 9b

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 Zone 9b

You may be interested in your other planting guides for Zone 9b.