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

The best time to plant lemon balm in Watertown can be figured out by reviewing the USDA zone info.

Planting Calendar for Lemon balm

Frost tolerance for lemon balm:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Lemon balm are one of those plants that can tolerate a tiny bit of cold weather which means that you can start planting them slightly earlier than more sensitive plants.

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

The last month that you can plant lemon balm and expect a good harvest is probably August. Any later than that and your lemon balm may not have a chance to grow to maturity. If you are starting your lemon balm indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Watertown. You should expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind that USDA zone info for Watertown is just an average and the actual date of last frost changes from year to year. Half of the time in Watertown last frost occurs after May 15 so make sure that you are prepared to cover your lemon balm if you have a late frost.

USDA Zone Info for Watertown

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Watertown

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