Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Green River can be reviewed to figure out 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 has passed.

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

The earliest that you can plant tithonia in Green River is May. However, you really should wait until June 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. If you wait any later than that and your tithonia may not have a chance to really do well. You can get started a couple of weeks earlier by starting your tithonia indoors.

Last Frost Date

The average date of last frost is May 15 in Green River. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Green River is an average the actual date of last frost changes from year to year. Half of the time in Green River there is a last frost after May 15 so be sure to be ready to protect your tithonia if you have a surprise late frost.

USDA Zone Info for Green River

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Green River

You may be interested in your other planting guides for Green River.