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 best time to plant watercress in Sullivan can be estimated by looking at the USDA zone info.

Planting Calendar for Watercress

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

Since watercress do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant watercress in Sullivan 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 watercress and expect a good harvest is probably August. If you wait any later than that and your watercress may not have a chance to really do well. If you are starting your watercress 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 April 15 in Sullivan. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Sullivan is an average the actual date of last frost changes from year to year. Half of the time in Sullivan last frost occurs after April 15 so make sure that you are prepared to cover your watercress in the event of a surprise late frost.

USDA Zone Info for Sullivan

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Sullivan

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