One of the first steps you take when you are figuring out 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.

By checking out the USDA zone info for Isle of Palms you should be able 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.

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 Isle of Palms 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 grow to maturity. Starting your watercress indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Isle of Palms. In the coldest months of winter you should expect an average low temperature of 15°F.

Always keep in mind that USDA zone info for Isle of Palms may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Isle of Palms you get a frost after March 15 so make sure that you are prepared to cover your watercress in the event of one of those late frosts.

USDA Zone Info for Isle of Palms

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Isle of Palms

You may be interested in your other planting guides for Isle of Palms.