When to Plant Dipladenia in Harrisburg, IL

Before planting it is a good idea to find your USDA Zone info to estimate 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.

By looking at the USDA zone info for Harrisburg you will be able to figure out when it's a good idea to plant dipladenia.


Planting Calendar for Dipladenia

Frost tolerance for dipladenia: Not tolerant of frost.
When to plant: After all chance of frost has passed.

Dipladenia are not cold tolerant which tells us that it's important to wait until it warms up after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant dipladenia
Possibly ok, but a risky time to plant dipladenia
Probably not a good time to plant dipladenia

The earliest that you can plant dipladenia in Harrisburg 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 really do well. Starting your dipladenia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Harrisburg. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Harrisburg may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Harrisburg you get a frost after April 15 be ready to cover your dipladenia if you have one of those late frosts.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°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 0°F.

Plants to Grow in Harrisburg

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