Before planting it is a good idea to find your USDA Zone info to estimate 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.

A way of making a decision about when to plant lettuce is to examine the USDA zone info for Harrisburg.

Planting Calendar for Lettuce

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

Since lettuce do well in moderate cold you can plant them just a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant lettuce in Harrisburg 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 lettuce and expect a good harvest is probably September. If you wait any later than that and your lettuce may not have a chance to fully mature. You can get started a few weeks earlier by starting your lettuce indoors.

Last Frost Date

The average date of last frost is April 15 in Harrisburg. In the coldest months of winter you can expect an average low temperature of 5°F.

Since the USDA zone info for Harrisburg may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Harrisburg last frost occurs after April 15 so be sure to be ready to cover your lettuce if you have a surprise late frost.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Harrisburg

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