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.

A way of making a decision about when it's a good idea to plant watercress is to refer to the USDA zone info for Katy.

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 are barely cold tolerant you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant watercress in Katy 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 grow to maturity. You can get started a couple of weeks earlier by starting your watercress indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Katy. In the coldest months of winter you should expect an average low temperature of 20°F.

Remember that USDA zone info for Katy may not be accurate from year to year and the actual date of last frost will vary from year to year. Since half of the time in Katy there is a last frost after February 15 be ready to cover your watercress if you have one of those late frosts.

USDA Zone Info for Katy

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 Katy

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