One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Mokena should be reviewed to determine when to plant sweet williams.

Planting Calendar for Sweet Williams

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

Sweet Williams tend to make it in some cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant sweet williams in Mokena 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 sweet williams and expect a good harvest is probably September. Any later than that and your sweet williams may not have a chance to really do well. You can get started a couple of weeks earlier by starting your sweet williams indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Mokena. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Mokena is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Mokena you get surprised by a frost after April 15 so just be sure to be ready to cover your sweet williams in the event of a late frost.

USDA Zone Info for Mokena

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Mokena

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