When to Plant Dipladenia in Harlan, IA

The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Harlan should be reviewed to figure out when you can plant dipladenia.


Planting Calendar for Dipladenia

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

Since dipladenia are not cold tolerant you need to wait until after the last 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 Harlan 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. You can get started a little bit earlier by starting your dipladenia indoors.

Last Frost Date

In Harlan the average date of last frost happens on April 15. You should expect an average low temperature of -20°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Harlan and it changes from year to year. Half of the time in Harlan there is a last frost after April 15 so be sure to be ready to cover your dipladenia in the event of one of those late frosts.

USDA Zone Info for Harlan

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 Harlan

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