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

You should be able to determine when to plant perilla by looking at the USDA zone info for San Bernardino.

Planting Calendar for Perilla

Frost tolerance for perilla:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's a bad idea to plant perilla until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant perilla 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 perilla and expect a good harvest is probably September. You probably don't want to wait any later than that or else your perilla may not have a chance to really do well. You can get started a few weeks earlier by starting your perilla indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in San Bernardino. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for San Bernardino is an average the actual date of last frost is different every year. Half of the time in San Bernardino last frost occurs after February 15 so make sure that you are prepared to cover your perilla if you have one of those late frosts.

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.