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

By looking at the USDA zone info for Plymouth you will be able to figure out when to plant romaine lettuce.

Planting Calendar for Romaine lettuce

Frost tolerance for romaine lettuce:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since romaine lettuce are very cold tolerant you can plant them much earlier in the year than other plants that might not handle the cold.

The earliest that you can plant romaine lettuce in Plymouth is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant romaine lettuce and expect a good harvest is probably September. If you wait any later than that and your romaine lettuce may not have a chance to grow to maturity. Starting your romaine lettuce indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Plymouth. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Plymouth is an average the actual date of last frost will vary from year to year. Since half of the time in Plymouth last frost occurs after April 15 be ready to cover your romaine lettuce in the event of one of those late frosts.

USDA Zone Info for Plymouth

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 Plymouth

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