The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Oakland can be used to estimate when it's the best time 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.

Watercress can survive in a tiny bit of cold which means that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant watercress in Oakland 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 fully mature. You can get started a few weeks earlier by starting your watercress indoors.

Last Frost Date

On average the last frost is on April 15 in Oakland. In the coldest months of winter you should expect an average low temperature of -5°F.

Just be sure 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 Oakland and it can change quite a bit from year to year. Since half of the time in Oakland there is a last frost after April 15 be ready to cover your watercress if you have a surprise late frost.

USDA Zone Info for Oakland

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Oakland

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