When can I plant Watercress in Zone 9b

One of the best tools that we have as gardeners to help us estimate our 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 our area.

You can figure out when it's possible to plant watercress in Zone 9b by referring to the USDA zone info.


Planting Calendar for Watercress

Frost tolerance for watercress: Tolerant of a very small amount of frost.
When you should plant them: Up to 3 weeks before last frost.

Since watercress are barely cold tolerant you can plant them slightly earlier in the year than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant watercress
Possibly ok, but a risky time to plant watercress
Probably not a good time to plant watercress

The earliest that you can plant watercress in Zone 9b 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. If you wait 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 few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Zone 9b. We should expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that USDA zone info for Zone 9b may not be accurate from year to year and our actual date of last frost is different every year. Since half of the time in Zone 9b we get surprised by a frost after February 15 be ready to cover your watercress in the event of a surprise late frost.

USDA Zone Info for Zone 9b

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 Low25°F
Highest Expected Low30°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 Zone 9b

You may be interested in our other planting guides for Zone 9b.