When can I plant Tithonia in Zone 4b

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

It's a good idea to determine when it's possible to plant tithonia by reviewing the USDA zone info for Zone 4b.


Planting Calendar for Tithonia

Frost tolerance for tithonia: Not tolerant of frost.
When you should plant them: After the last frost.

Since tithonia are not cold tolerant you have to wait until after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant tithonia
Possibly ok, but a risky time to plant tithonia
Probably not a good time to plant tithonia

The earliest that you can plant tithonia in Zone 4b 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. Starting your tithonia indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4b. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Zone 4b is an average and our actual date of last frost is different every year. Half of the time in Zone 4b it frosts late in the year after May 15 so make sure that you are ready to protect your tithonia if we have a late frost.

USDA Zone Info for Zone 4b

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 Zone 4b

You may be interested in our other planting guides for Zone 4b.