One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of figuring out when you can plant watercress is to consult the USDA zone info for River Grove.

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 moderate cold which tells us that you can get them planted just a bit earlier than other frost tender plants.

The earliest that you can plant watercress in River Grove 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 really do well. You can get started a little bit earlier by starting your watercress indoors.

Last Frost Date

On average the last frost is on April 15 in River Grove. You should expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for River Grove is just an average and the actual date of last frost is different every year. Half of the time in River Grove there is a last frost after April 15 so make sure that you are prepared to protect your watercress in the event of a late frost.

USDA Zone Info for River Grove

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 River Grove

You may be interested in your other planting guides for River Grove.