The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The best time to plant tithonia in Douglas can be estimated by referring to the USDA zone info.

Planting Calendar for Tithonia

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

It's a bad idea to plant tithonia until after the last frost because they are not cold tolerant.

The earliest that you can plant tithonia in Douglas 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. If you are starting your tithonia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Douglas and it changes from year to year. Half of the time in Douglas there is a last frost after March 15 so make sure that you are ready to protect your tithonia if you have one of those late frosts.

USDA Zone Info for Douglas

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Douglas

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