One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when it's a good idea to plant sweet williams is to consult the USDA zone info for Woburn.

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 well in moderate cold which tells us that you can plant them a little bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant sweet williams in Woburn 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 grow to maturity. You can get started a little bit earlier by starting your sweet williams indoors.

Last Frost Date

The average date of last frost is April 15 in Woburn. It might get as low as -10°F during the coldest months of winter.

Keep in mind that USDA zone info for Woburn is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Woburn you get a frost after April 15 be ready to protect your sweet williams if you have a late frost.

USDA Zone Info for Woburn

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 Woburn

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