The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Merrill you can figure out when it's a good idea to plant lettuce by using the USDA zone info.

Planting Calendar for Lettuce

Frost tolerance for lettuce:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Lettuce do ok in mild cold which means that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant lettuce in Merrill 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 lettuce and expect a good harvest is probably August. Any later than that and your lettuce may not have a chance to really do well. Starting your lettuce indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Merrill the average date of last frost happens on May 15. You should expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Merrill is an average the actual date of last frost changes from year to year. Half of the time in Merrill you get a frost after May 15 so always be ready to cover your lettuce if you have one of those late frosts.

USDA Zone Info for Merrill

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Merrill

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