One of the first steps you take when you are determining your gardening schedule is find your 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.

By checking out the USDA zone info for New London 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.

Dipladenia are not cold tolerant which tells us that you really should wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant dipladenia in New London 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. Any later than that and your dipladenia may not have a chance to grow to maturity. 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

On average the last frost has passed is on April 15 in New London. You should expect an average low temperature of -20°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for New London and it changes from year to year. Half of the time in New London there is a last frost after April 15 so make sure that you are ready to protect your dipladenia if you have one of those late frosts.

USDA Zone Info for New London

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°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 -15°F.

Plants to Grow in New London

You may be interested in your other planting guides for New London.