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

In Watertown you can figure out when it's the best time to plant cerastium by checking out the USDA zone info.

Planting Calendar for Cerastium

Frost tolerance for cerastium:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Cerastium do well in some cold which means that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant cerastium in Watertown is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant cerastium and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cerastium may not have a chance to fully mature. Starting your cerastium indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Watertown. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Watertown is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Watertown it frosts late in the year after May 15 so just be sure to be ready to cover your cerastium in the event of one of those late frosts.

USDA Zone Info for Watertown

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Watertown

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