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When to Plant Common hollyhock in Denison, IA

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to figure out when it's the best time to plant common hollyhock by checking out the USDA zone info for Denison.


Planting Calendar for Common hollyhock

Frost tolerance for common hollyhock: Tolerant of some frost.
When to plant: Up to 5 weeks before last frost.

You can plant common hollyhock just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

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

The earliest that you can plant common hollyhock in Denison is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant common hollyhock and expect a good harvest is probably September. Any later than that and your common hollyhock may not have a chance to grow to maturity. If you are starting your common hollyhock indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Denison the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Denison and it changes from year to year. Half of the time in Denison it frosts late in the year after April 15 so just be sure to be ready to cover your common hollyhock in the event of one of those late frosts.

USDA Zone Info for Denison

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 Denison

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