Before planting it is a good idea to find your USDA Zone info to figure out 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 first opportunity to plant tithonia in Pella can be determined by using the USDA zone info.

Planting Calendar for Tithonia

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

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

The earliest that you can plant tithonia in Pella 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. If you wait any later than that and your tithonia may not have a chance to fully mature. You can get started a few weeks earlier by starting your tithonia indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Pella. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Pella is not always accurate the actual date of last frost is different every year. Since half of the time in Pella there is a last frost after April 15 be ready to cover your tithonia if you have one of those late frosts.

USDA Zone Info for Pella

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 Pella

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