Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to figure out when it's a good idea to plant romaine lettuce by using the USDA zone info for De Pere.

Planting Calendar for Romaine lettuce

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

You can plant romaine lettuce quite a bit earlier in the year because they are very cold tolerant.

The earliest that you can plant romaine lettuce in De Pere 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. You probably don't want to wait any later than that or else your romaine lettuce may not have a chance to fully mature. You can get started a little bit earlier by starting your romaine lettuce indoors.

Last Frost Date

In De Pere the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Remember that USDA zone info for De Pere is just an average and the actual date of last frost is different every year. Since half of the time in De Pere you get surprised by a frost after April 15 be ready to protect your romaine lettuce in the event of a surprise late frost.

USDA Zone Info for De Pere

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in De Pere

You may be interested in your other planting guides for De Pere.