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

The USDA zone info for Marion can be read to estimate when it's possible 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.

You can plant watercress a bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant watercress in Marion 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. If you are starting your watercress indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Marion. In the coldest months of winter you should expect an average low temperature of 5°F.

Remember that USDA zone info for Marion is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Marion it frosts late in the year after April 15 be ready to cover your watercress in the event of a late frost.

USDA Zone Info for Marion

Here is the info for USDA Zone 7b.

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

Plants to Grow in Marion

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