One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Sonoma you can figure out when it's possible to plant garden cress by looking at the USDA zone info.

Planting Calendar for Garden cress

Frost tolerance for garden cress:	Not tolerant of frost.
When to plant:	After the last frost.

It's probably a bad idea to plant garden cress until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant garden cress in Sonoma 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 garden cress and expect a good harvest is probably September. Any later than that and your garden cress may not have a chance to grow to maturity. If you are starting your garden cress indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Sonoma. It might get as low as 25°F during the coldest months of winter.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Sonoma and it will vary from year to year. Half of the time in Sonoma there is a last frost after February 15 so just be sure to be ready to cover your garden cress if you have a surprise late frost.

USDA Zone Info for Sonoma

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 Sonoma

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