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When to Plant Common hollyhock in Glen Carbon, IL

One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Glen Carbon can be used to figure out when it's a good idea to plant common hollyhock.


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 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 Glen Carbon 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 Glen Carbon the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Glen Carbon may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Glen Carbon last frost occurs after April 15 so make sure that you are ready to cover your common hollyhock in the event of a surprise late frost.

USDA Zone Info for Glen Carbon

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-10°F
Highest Expected Low-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Glen Carbon

You may be interested in your other planting guides for Glen Carbon.