When to Plant Dahlia in Hiawatha, 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.

By looking at the USDA zone info for Hiawatha it's a good idea to determine when it's a good idea to plant dahlia.


Planting Calendar for Dahlia

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

Since dahlia require warm weather it's necessary to wait until after the last frost before you can plant them.

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

The earliest that you can plant dahlia in Hiawatha 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 dahlia and expect a good harvest is probably August. Any later than that and your dahlia may not have a chance to really do well. You can get started a little bit earlier by starting your dahlia indoors.

Last Frost Date

The average date of last frost is April 15 in Hiawatha. In the coldest months of winter you should expect an average low temperature of -20°F.

Since the USDA zone info for Hiawatha may not be accurate from year to year the actual date of last frost will vary from year to year. Since half of the time in Hiawatha it frosts late in the year after April 15 be ready to protect your dahlia in the event of one of those late frosts.

USDA Zone Info for Hiawatha

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 Hiawatha

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