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.

A common way of estimating when to plant watercress is to refer to the USDA zone info for Urbandale.

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 well in mild cold which means that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant watercress in Urbandale 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 fully mature. 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

In Urbandale the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Urbandale and it can change quite a bit from year to year. Since half of the time in Urbandale you get a frost after April 15 be ready to protect your watercress in the event of a late frost.

USDA Zone Info for Urbandale

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Urbandale

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