Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when it's the best time to plant sweet williams by using the USDA zone info for Cambridge.

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 tend to make it in mild cold which tells us that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant sweet williams in Cambridge 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. If you wait any later than that and your sweet williams may not have a chance to really do well. You can get started a little bit earlier by starting your sweet williams indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Cambridge. In the coldest months of winter you can expect an average low temperature of -5°F.

Remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Cambridge and it changes from year to year. Half of the time in Cambridge there is a last frost after April 15 so be sure to be ready to cover your sweet williams if you have a late frost.

USDA Zone Info for Cambridge

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 Cambridge

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