The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Willits can be reffered to in order to determine when to plant watercress.

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 a bit earlier in the year than more sensitive plants.

The earliest that you can plant watercress in Willits is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant watercress and expect a good harvest is probably September. Any later than that and your watercress may not have a chance to really do well. If you are starting your watercress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Willits the average date of last frost happens on February 15. In the coldest months of winter you should expect an average low temperature of 20°F.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Willits and it can change quite a bit from year to year. Half of the time in Willits there is a last frost after February 15 so make sure that you are prepared to cover your watercress in the event of a surprise late frost.

USDA Zone Info for Willits

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°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 25°F.

Plants to Grow in Willits

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