The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Watertown it's a good idea to estimate when it's a good idea to plant violas.

Planting Calendar for Violas

Frost tolerance for violas:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Violas do ok in quite a bit of cold which means that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant violas 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 violas and expect a good harvest is probably August. Any later than that and your violas may not have a chance to fully mature. You can get started a few weeks earlier by starting your violas indoors.

Last Frost Date

On average the last frost is on May 15 in Watertown. You should expect an average low temperature of -25°F in the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Watertown and it can change quite a bit from year to year. Half of the time in Watertown you get a frost after May 15 so always be ready to cover your violas if you have 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.