The USDA Zone info is a great tool for gardeners to help us estimate your gardening 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 Winthrop Harbor can be reffered to in order to estimate 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.

You can plant watercress just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant watercress in Winthrop Harbor 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 really do well. You can get started a couple of weeks earlier by starting your watercress indoors.

Last Frost Date

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

It's important to remember that USDA zone info for Winthrop Harbor is just an average and the actual date of last frost is different every year. Since half of the time in Winthrop Harbor it frosts late in the year after April 15 be ready to protect your watercress if you have a surprise late frost.

USDA Zone Info for Winthrop Harbor

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Winthrop Harbor

You may be interested in your other planting guides for Winthrop Harbor.