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

It's possible to estimate when it's possible to plant asparagus lettuce by looking at the USDA zone info for San Bernardino.

Planting Calendar for Asparagus lettuce

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

Asparagus lettuce are not cold tolerant which means that you need to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant asparagus lettuce in San Bernardino 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. You probably don't want to wait any later than that or else your asparagus lettuce may not have a chance to fully mature. If you are starting your asparagus lettuce indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In San Bernardino the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for San Bernardino and it can change quite a bit from year to year. Half of the time in San Bernardino you get a frost after February 15 so be sure to be ready to protect your asparagus lettuce in the event of a surprise late frost.

USDA Zone Info for San Bernardino

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°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 30°F.

Plants to Grow in San Bernardino

You may be interested in your other planting guides for San Bernardino.