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 referring to the USDA zone info for Princeton it's a good idea to figure out when to plant dipladenia.

Planting Calendar for Dipladenia

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

You can not plant dipladenia until after the last frost because they are not cold tolerant.

The earliest that you can plant dipladenia in Princeton 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 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. Starting your dipladenia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Princeton. In the coldest months of winter you can expect an average low temperature of -30°F.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Princeton and it will vary from year to year. Since half of the time in Princeton you get a frost after May 15 be ready to protect your dipladenia if you have a surprise late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Princeton

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