Before planting it is a good idea to find your USDA Zone info to estimate 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 Zone 5a can be reffered to in order to estimate when it's possible to plant tithonia.

Planting Calendar for Tithonia

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

Since tithonia are not cold tolerant you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant tithonia in Zone 5a is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant tithonia and expect a good harvest is probably August. Any later than that and your tithonia may not have a chance to fully mature. You can get started a little bit earlier by starting your tithonia indoors.

Last Frost Date

In Zone 5a the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Zone 5a and it can change quite a bit from year to year. Half of the time in Zone 5a last frost occurs after April 15 so be sure to be ready to cover your tithonia in the event of one of those late frosts.

USDA Zone Info for Zone 5a

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in Zone 5a

You may be interested in your other planting guides for Zone 5a.