One of the best tools that you have as gardeners to help us figure out 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.

You should be able to figure out when you can plant watercress by looking at the USDA zone info for Austin.

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 more sensitive plants.

The earliest that you can plant watercress in Austin 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. If you wait any later than that and your watercress may not have a chance to really do well. You can get started a couple of weeks earlier by starting your watercress indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Austin. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Austin may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Austin you get surprised by a frost after April 15 so just be sure to be ready to cover your watercress in the event of a surprise late frost.

USDA Zone Info for Austin

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Austin

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