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 Clayton can be read to determine when to plant watercress.

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.

Watercress do ok in moderate cold which tells us that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant watercress in Clayton 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. You probably don't want to wait any later than that or else your watercress may not have a chance to grow to maturity. Starting your watercress indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Clayton. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for Clayton is not always accurate the actual date of last frost is different every year. Since half of the time in Clayton you get surprised by a frost after April 15 be ready to cover your watercress if you have one of those late frosts.

USDA Zone Info for Clayton

Here is the info for USDA Zone 7b.

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

Plants to Grow in Clayton

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