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

A common way of making a decision about when it's a good idea to plant sweet williams is to look at the USDA zone info for Vandalia.

Planting Calendar for Sweet Williams

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

Since sweet williams are one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

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

Last Frost Date

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

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Vandalia and it can change quite a bit from year to year. Since half of the time in Vandalia there is a last frost after April 15 be ready to cover your sweet williams in the event of one of those late frosts.

USDA Zone Info for Vandalia

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 Vandalia

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