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.

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

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 more sensitive plants.

The earliest that you can plant watercress in Hearne 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. If you are starting your watercress indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Hearne and it is different every year. Since half of the time in Hearne you get a frost after March 15 be ready to protect your watercress in the event of a late frost.

USDA Zone Info for Hearne

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Hearne

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