One of the best tools that you have as gardeners to help us determine 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.

In Grimes you can determine when it's the best time to plant watercress by checking out 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.

Watercress are barely cold tolerant which means that you can get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant watercress in Grimes 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. Starting your watercress indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Grimes. In the coldest months of winter you can expect an average low temperature of -20°F.

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

USDA Zone Info for Grimes

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 Grimes

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