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

The USDA zone info for Portland can be reviewed to determine when it's the best time to plant perilla.

Planting Calendar for Perilla

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

You can not plant perilla until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant perilla in Portland 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. Any later than that and your perilla may not have a chance to grow to maturity. You can get started a little bit earlier by starting your perilla indoors.

Last Frost Date

The average date of last frost is February 15 in Portland. It might get as low as 25°F during the coldest months of winter.

Always keep in mind that USDA zone info for Portland is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Portland you get surprised by a frost after February 15 so make sure that you are ready to protect your perilla if you have one of those late frosts.

USDA Zone Info for Portland

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 Portland

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