The USDA Zone info is a great tool for gardeners to help us figure out 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.

The USDA zone info for Plymouth can be reffered to in order to determine when it's a good idea to plant bittercress.

Planting Calendar for Bittercress

Frost tolerance for bittercress:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Bittercress do ok in very little cold which means that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant bittercress in Plymouth 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 bittercress and expect a good harvest is probably August. Any later than that and your bittercress may not have a chance to really do well. You can get started a couple of weeks earlier by starting your bittercress indoors.

Last Frost Date

In Plymouth the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Plymouth may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Plymouth last frost occurs after April 15 be ready to cover your bittercress if you have a surprise late frost.

USDA Zone Info for Plymouth

Here is the info for USDA Zone 5b.

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

Plants to Grow in Plymouth

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