One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant calendula in Dayton should be estimated by referring to the USDA zone info.

Planting Calendar for Calendula

Frost tolerance for calendula:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Calendula are moderately cold tolerant which means that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant calendula in Dayton is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant calendula and expect a good harvest is probably October. If you wait any later than that and your calendula may not have a chance to really do well. Starting your calendula indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Dayton the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Dayton is just an average the actual date of last frost is different every year. Half of the time in Dayton you get a frost after February 15 so make sure that you are ready to protect your calendula in the event of one of those late frosts.

USDA Zone Info for Dayton

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Dayton

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