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When to Plant Sweet Sultan in Harrisburg, IL

One of the first steps you take when you are determining 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.

You can figure out when it's possible to plant sweet sultan in Harrisburg by reviewing the USDA zone info.


Planting Calendar for Sweet Sultan

Frost tolerance for sweet sultan: Tolerant of a very small amount of frost.
When to plant: Up to 3 weeks before last frost.

Sweet Sultan are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can plant them slightly earlier than plants that are more sensitive to the cold.

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

The earliest that you can plant sweet sultan in Harrisburg is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant sweet sultan and expect a good harvest is probably August. If you wait any later than that and your sweet sultan may not have a chance to really do well. If you are starting your sweet sultan indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Keep in mind that USDA zone info for Harrisburg may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Harrisburg it frosts late in the year after April 15 be ready to protect your sweet sultan if you have one of those late frosts.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-5°F
Highest Expected Low0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Harrisburg

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