One of the first steps you take when you are making a decision about 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.

The USDA zone info for Chelsea should be reviewed to figure out when it's the best time to plant sweet williams.

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 other plants that might not handle the cold.

The earliest that you can plant sweet williams in Chelsea 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 little bit earlier by starting your sweet williams indoors.

Last Frost Date

In Chelsea the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

It's important to remember that USDA zone info for Chelsea is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Chelsea last frost occurs after April 15 be ready to cover your sweet williams in the event of a surprise late frost.

USDA Zone Info for Chelsea

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 Chelsea

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