One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant dipladenia in Petersburg should be figured out by using the USDA zone info.

Planting Calendar for Dipladenia

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

You really shouldn't plant dipladenia until after all chance of frost has passed because they require warm weather.

The earliest that you can plant dipladenia in Petersburg 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 dipladenia and expect a good harvest is probably August. If you wait any later than that and your dipladenia may not have a chance to really do well. If you are starting your dipladenia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Petersburg the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Petersburg and it changes from year to year. Since half of the time in Petersburg you get a frost after April 15 be ready to cover your dipladenia if you have a late frost.

USDA Zone Info for Petersburg

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Petersburg

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