One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Sullivan you should be able to figure out when it's the best time to plant dipladenia.

Planting Calendar for Dipladenia

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

Since dipladenia do not do well in cold weather it's important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant dipladenia in Sullivan 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. You probably don't want to wait any later than that or else your dipladenia may not have a chance to fully mature. If you are starting your dipladenia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Sullivan. You should expect an average low temperature of 5°F in the coldest months of winter.

Since the USDA zone info for Sullivan may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Sullivan you get a frost after April 15 be ready to cover your dipladenia in the event of a late frost.

USDA Zone Info for Sullivan

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 Sullivan

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