The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant watercress in Merrillville should be estimated by looking at the USDA zone info.

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 are barely cold tolerant you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant watercress in Merrillville 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. If you wait any later than that and your watercress may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your watercress indoors.

Last Frost Date

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

Since the USDA zone info for Merrillville may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Merrillville you get surprised by a frost after April 15 so always be ready to cover your watercress in the event of one of those late frosts.

USDA Zone Info for Merrillville

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 Merrillville

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