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

The USDA zone info for Watertown should be reffered to in order to determine when to plant flowering kale.

Planting Calendar for Flowering Kale

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

Flowering Kale do well in moderate cold which means that you can plant them earlier than other frost tender plants.

The earliest that you can plant flowering kale 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 flowering kale and expect a good harvest is probably August. Any later than that and your flowering kale may not have a chance to fully mature. If you are starting your flowering kale indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Watertown and it changes from year to year. Half of the time in Watertown it frosts late in the year after May 15 so make sure that you are prepared to cover your flowering kale if you have a late frost.

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.