One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

By referring to the USDA zone info for Chelsea it's a good idea 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.

Sweet Williams are moderately cold tolerant which means that you can plant them a little bit earlier than more sensitive plants.

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 really do well. 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 Chelsea. You can expect an average low temperature of -5°F in the coldest months of winter.

Remember that USDA zone info for Chelsea may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Chelsea you get a frost after April 15 be ready to protect your sweet williams if you have one of those late frosts.

USDA Zone Info for Chelsea

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 Chelsea

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