Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Donna should be used to estimate when you can plant tithonia.

Planting Calendar for Tithonia

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

It's a bad idea to plant tithonia until after the last frost because they do not do well in cold weather.

The earliest that you can plant tithonia in Donna 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. Starting your tithonia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Donna and it changes from year to year. Half of the time in Donna it frosts late in the year after February 15 so just be sure to be ready to protect your tithonia in the event of one of those late frosts.

USDA Zone Info for Donna

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 Donna

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