The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Waukesha you should be able to figure out when it's a good idea 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.

It's probably not a good idea to plant perilla until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant perilla in Waukesha 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. You probably don't want to wait any later than that or else your perilla may not have a chance to grow to maturity. If you are starting your perilla indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Waukesha. It might get as low as -15°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Waukesha and it will vary from year to year. Half of the time in Waukesha last frost occurs after April 15 so make sure that you are prepared to cover your perilla in the event of one of those late frosts.

USDA Zone Info for Waukesha

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

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

Plants to Grow in Waukesha

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