Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Sioux Center you can figure out when you can 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.

Sweet Williams do ok in mild cold which tells us that you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant sweet williams in Sioux Center 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 little bit earlier by starting your sweet williams indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Sioux Center. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Sioux Center is not always accurate the actual date of last frost is different every year. Half of the time in Sioux Center last frost occurs after April 15 so be sure to be ready to protect your sweet williams if you have one of those late frosts.

USDA Zone Info for Sioux Center

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 Sioux Center

You may be interested in your other planting guides for Sioux Center.