One of the best tools that you have as gardeners to help us estimate 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.

One way of estimating when it's possible to plant tithonia is to refer to the USDA zone info for Fort Collins.

Planting Calendar for Tithonia

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

It's probably not a good idea to plant tithonia until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant tithonia in Fort Collins 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 couple of weeks earlier by starting your tithonia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Fort Collins. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Fort Collins and it is different every year. Since half of the time in Fort Collins you get a frost after April 15 be ready to protect your tithonia in the event of a late frost.

USDA Zone Info for Fort Collins

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 Fort Collins

You may be interested in your other planting guides for Fort Collins.