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.

The first opportunity to plant watercress in Colusa can be determined by reviewing 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.

You can plant watercress slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant watercress in Colusa 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. You probably don't want to wait any later than that or else your watercress may not have a chance to fully mature. You can get started a little bit earlier by starting your watercress indoors.

Last Frost Date

On average all chance of frost has passed is on February 15 in Colusa. In the coldest months of winter you should expect an average low temperature of 25°F.

Keep in mind that USDA zone info for Colusa is an average and the actual date of last frost changes from year to year. Since half of the time in Colusa there is a last frost after February 15 be ready to protect your watercress in the event of a surprise late frost.

USDA Zone Info for Colusa

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Colusa

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