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.

The USDA zone info for Harrison should be reffered to in order to figure out when you can 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 tend to make it in some cold which means that you can plant them just a tiny bit earlier in the year than more sensitive plants.

The earliest that you can plant watercress in Harrison 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 little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Harrison. You should expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that USDA zone info for Harrison is an average and the actual date of last frost will vary from year to year. Since half of the time in Harrison you get a frost after April 15 be ready to protect your watercress in the event of a late frost.

USDA Zone Info for Harrison

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 Harrison

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