Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Philadelphia can be reffered to in order to estimate when to plant perilla.

Planting Calendar for Perilla

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

Since perilla require warm weather you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant perilla in Philadelphia is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant perilla and expect a good harvest is probably August. Any later than that and your perilla may not have a chance to fully mature. You can get started a little bit earlier by starting your perilla indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Philadelphia. In the coldest months of winter you should expect an average low temperature of 10°F.

Since the USDA zone info for Philadelphia is not always accurate the actual date of last frost is different every year. Half of the time in Philadelphia you get surprised by a frost after March 15 so make sure that you are prepared to protect your perilla if you have one of those late frosts.

USDA Zone Info for Philadelphia

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Philadelphia

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