When to Plant Canna in Harlan, IA

The USDA Zone info is a great tool for gardeners to help us figure out 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.

It's a good idea to determine when it's possible to plant canna by using the USDA zone info for Harlan.


Planting Calendar for Canna

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

Since canna do not do well in cold weather it's necessary to wait until after all chance of frost has passed before you can plant them.

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

The earliest that you can plant canna 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 canna and expect a good harvest is probably August. If you wait any later than that and your canna may not have a chance to grow to maturity. If you are starting your canna indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Harlan is an average and the actual date of last frost will vary from year to year. Half of the time in Harlan it frosts late in the year after April 15 so always be ready to cover your canna if you have 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.