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

The USDA zone info for Green River should be used to determine when it's the best time to plant iceberg lettuce.

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.

Iceberg lettuce can survive in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant iceberg lettuce in Green River is April. However, you really should wait until May 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. If you wait any later than that and your iceberg lettuce may not have a chance to fully mature. Starting your iceberg lettuce indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Green River. It might get as low as -25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Green River is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Green River you get surprised by a frost after May 15 so just be sure to be ready to cover your iceberg lettuce if you have a surprise late frost.

USDA Zone Info for Green River

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Green River

You may be interested in your other planting guides for Green River.