One of the first steps you take when you are determining your gardening schedule is find your 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.

It's a good idea to determine when it's a good idea to plant rock cress by using the USDA zone info for Watertown.

Planting Calendar for Rock Cress

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

You can plant rock cress much earlier in the year because they do well in cold.

The earliest that you can plant rock cress 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 rock cress and expect a good harvest is probably August. If you wait any later than that and your rock cress may not have a chance to really do well. If you are starting your rock cress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Watertown may not be accurate from year to year and the actual date of last frost is different every year. Since half of the time in Watertown last frost occurs after May 15 be ready to cover your rock cress if you have a surprise 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.