Before planting it is a good idea to find your USDA Zone info to estimate 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.

A common way of getting a good idea when it's possible to plant watercress is to check out the USDA zone info for Roanoke.

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 a bit earlier in the year than more sensitive plants.

The earliest that you can plant watercress in Roanoke 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 fully mature. 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 Roanoke the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Roanoke and it changes from year to year. Half of the time in Roanoke it frosts late in the year after April 15 so make sure that you are ready to cover your watercress if you have a late frost.

USDA Zone Info for Roanoke

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 Roanoke

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