The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In South Holland you can figure out when it's the best time to plant sweet williams by using the USDA zone info.

Planting Calendar for Sweet Williams

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

You can plant sweet williams a little earlier in the year because they do well in moderate cold.

The earliest that you can plant sweet williams in South Holland 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. If you wait any later than that and your sweet williams may not have a chance to fully mature. You can get started a few weeks earlier by starting your sweet williams indoors.

Last Frost Date

In South Holland 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.

Just be sure to remember that USDA zone info for South Holland is an average and the actual date of last frost changes from year to year. Half of the time in South Holland there is a last frost after April 15 so be sure to be ready to protect your sweet williams in the event of a surprise late frost.

USDA Zone Info for South Holland

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 South Holland

You may be interested in your other planting guides for South Holland.