Before planting it is a good idea to find your USDA Zone info to determine 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 catharanthus in Dayton should be figured out by using the USDA zone info.

Planting Calendar for Catharanthus

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

Since catharanthus do not do well in cold weather it is important to wait until after the last frost before you can plant them.

The earliest that you can plant catharanthus in Dayton 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 catharanthus and expect a good harvest is probably August. Any later than that and your catharanthus may not have a chance to fully mature. If you are starting your catharanthus indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Dayton the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Dayton is just an average the actual date of last frost will vary from year to year. Half of the time in Dayton it frosts late in the year after May 15 so just be sure to be ready to cover your catharanthus in the event of a late frost.

USDA Zone Info for Dayton

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 Dayton

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