One of the best tools that you have as gardeners to help us figure out 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.

In Humboldt you can figure out when it's a good idea to plant iceberg lettuce by looking at the USDA zone info.

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 are one of those plants that can tolerate a tiny bit of cold weather which tells us that you can get them planted just a bit earlier than more sensitive plants.

The earliest that you can plant iceberg lettuce in Humboldt 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. If you wait any later than that and your iceberg lettuce may not have a chance to really do well. Starting your iceberg lettuce indoors is a great way to get them started a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Humboldt 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 Humboldt you get a frost after April 15 so be sure to be ready to protect your iceberg lettuce if you have a late frost.

USDA Zone Info for Humboldt

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 Humboldt

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