One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's a good idea to plant asparagus lettuce is to refer to the USDA zone info for Sonora.

Planting Calendar for Asparagus lettuce

Frost tolerance for asparagus lettuce:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since asparagus lettuce are not cold tolerant you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant asparagus lettuce in Sonora 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 asparagus lettuce and expect a good harvest is probably September. If you wait any later than that and your asparagus lettuce may not have a chance to fully mature. Starting your asparagus lettuce indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost is on February 15 in Sonora. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Sonora is an average the actual date of last frost will vary from year to year. Since half of the time in Sonora last frost occurs after February 15 be ready to protect your asparagus lettuce in the event of one of those late frosts.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

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

Plants to Grow in Sonora

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