Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to figure out when it's a good idea to plant watercress by looking at the USDA zone info for Durham.

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 are one of those plants that can tolerate a tiny bit of cold weather which means that you can get them planted just a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant watercress in Durham 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. If you are starting your watercress indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Durham the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Durham may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Durham last frost occurs after April 15 be ready to cover your watercress if you have one of those late frosts.

USDA Zone Info for Durham

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 Durham

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