One of the first steps you take when you are determining 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 best time to plant romaine lettuce in Berwyn should be figured out by using the USDA zone info.

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 are one of those plants that can tolerate quite a bit of cold weather which means that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant romaine lettuce in Berwyn 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. Any later than that and your romaine lettuce may not have a chance to fully mature. Starting your romaine lettuce indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Always keep in mind that USDA zone info for Berwyn is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Berwyn you get surprised by a frost after April 15 be ready to cover your romaine lettuce if you have one of those late frosts.

USDA Zone Info for Berwyn

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 Berwyn

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