One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 Yorkville should be looked at to determine when it's a good idea to plant tithonia.

Planting Calendar for Tithonia

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

Since tithonia do not do well in cold weather you really should wait until after the last frost before you can plant them.

The earliest that you can plant tithonia in Yorkville 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 grow to maturity. You can get started a little bit earlier by starting your tithonia indoors.

Last Frost Date

The average date of last frost is April 15 in Yorkville. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Yorkville is just an average the actual date of last frost changes from year to year. Since half of the time in Yorkville there is a last frost after April 15 be ready to cover your tithonia in the event of a surprise late frost.

USDA Zone Info for Yorkville

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Yorkville

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