One of the first steps you take when you are figuring out 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.

One way of getting a good idea when it's a good idea to plant sweet williams is to examine the USDA zone info for Stillwater.

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 just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant sweet williams in Stillwater is March. However, you really should wait until April 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 August. 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

On average the last frost when the weather gets warmer is on May 15 in Stillwater. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Stillwater is an average the actual date of last frost changes from year to year. Since half of the time in Stillwater you get a frost after May 15 be ready to cover your sweet williams in the event of a late frost.

USDA Zone Info for Stillwater

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Stillwater

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