One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Watertown should be read to figure out when it's the best time to plant streptocarpella.

Planting Calendar for Streptocarpella

Frost tolerance for streptocarpella:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Streptocarpella are not cold tolerant which means that you really should wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant streptocarpella 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 streptocarpella and expect a good harvest is probably August. Any later than that and your streptocarpella may not have a chance to really do well. You can get started a couple of weeks earlier by starting your streptocarpella indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Watertown. You can expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Watertown is not always accurate and the actual date of last frost changes from year to year. Half of the time in Watertown last frost occurs after April 15 so just be sure to be ready to cover your streptocarpella if you have one of those late frosts.

USDA Zone Info for Watertown

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 Watertown

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