One of the first steps you take when you are determining 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 making a decision about when it's possible to plant sweet williams is to examine the USDA zone info for Carnegie.

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 are moderately cold tolerant which means that you can plant them a little bit earlier than other plants that might not handle the cold.

The earliest that you can plant sweet williams in Carnegie 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 few weeks earlier by starting your sweet williams indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Carnegie. It might get as low as -5°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Carnegie and it can change quite a bit from year to year. Half of the time in Carnegie last frost occurs after April 15 so make sure that you are prepared to protect your sweet williams if you have one of those late frosts.

USDA Zone Info for Carnegie

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Carnegie

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