One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's possible to plant sweet williams in Vandalia by referring to 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 means that you can plant them a bit earlier in the year than more sensitive plants.

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. You probably don't want to wait any later than that or else 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

On average the last frost is on April 15 in Vandalia. You should expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Vandalia and it can change quite a bit from year to year. Half of the time in Vandalia you get a frost after April 15 so make sure that you are prepared to protect your sweet williams if you have a surprise late frost.

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.