One of the first steps you take when you are estimating your gardening schedule is find your 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.

A common way of determining when to plant sweet williams is to look at the USDA zone info for Springfield.

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 moderate cold which means that you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant sweet williams in Springfield 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 grow to maturity. You can get started a couple of weeks earlier by starting your sweet williams indoors.

Last Frost Date

The average date of last frost is April 15 in Springfield. In the coldest months of winter you can expect an average low temperature of -10°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Springfield and it is different every year. Since half of the time in Springfield you get surprised by a frost after April 15 be ready to cover your sweet williams if you have a surprise late frost.

USDA Zone Info for Springfield

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 Springfield

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