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.

By checking out the USDA zone info for Conshohocken you should be able to determine 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.

Watercress can survive in very little cold which means that you can plant them just a tiny bit earlier in the year than other frost tender plants.

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

Last Frost Date

The average date of last frost is April 15 in Conshohocken. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Conshohocken is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Conshohocken 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 late frost.

USDA Zone Info for Conshohocken

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Conshohocken

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