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.

By checking out the USDA zone info for Marshfield it's possible to estimate when it's the best time 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 very little cold which means that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant watercress in Marshfield is April. However, you really should wait until May 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 really do well. 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 May 15 in Marshfield. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Marshfield is just an average the actual date of last frost will vary from year to year. Since half of the time in Marshfield you get surprised by a frost after May 15 be ready to cover your watercress in the event of a late frost.

USDA Zone Info for Marshfield

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Marshfield

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