One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when to plant watercress is to examine the USDA zone info for Hayden.

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 do ok in moderate cold you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant watercress in Hayden 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. Any later than that and your watercress may not have a chance to fully mature. You can get started a few weeks earlier by starting your watercress indoors.

Last Frost Date

In Hayden the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

It's important to remember that USDA zone info for Hayden is an average and the actual date of last frost is different every year. Half of the time in Hayden there is a last frost after April 15 so be sure to be ready to protect your watercress in the event of a late frost.

USDA Zone Info for Hayden

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Hayden

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