One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

One way of determining when it's the best time to plant iceberg lettuce is to look at the USDA zone info for Springfield.

Planting Calendar for Iceberg lettuce

Frost tolerance for iceberg lettuce:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since iceberg lettuce are barely cold tolerant you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant iceberg lettuce in Springfield 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 iceberg lettuce and expect a good harvest is probably August. Any later than that and your iceberg lettuce may not have a chance to grow to maturity. If you are starting your iceberg lettuce indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Springfield. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Springfield is an average the actual date of last frost is different every year. Half of the time in Springfield you get a frost after April 15 so be sure to be ready to protect your iceberg lettuce if you have a surprise late frost.

USDA Zone Info for Springfield

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Springfield

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