One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. 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 Ann Arbor should be reffered to in order to figure out when it's possible 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.

Romaine lettuce do well in cold which tells us that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant romaine lettuce in Ann Arbor 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 really do well. Starting your romaine lettuce indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Ann Arbor the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Ann Arbor and it will vary from year to year. Half of the time in Ann Arbor there is a last frost after April 15 so be sure to be ready to protect your romaine lettuce if you have a late frost.

USDA Zone Info for Ann Arbor

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 Ann Arbor

You may be interested in your other planting guides for Ann Arbor.