Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's a good idea to plant bishop's weed in Philadelphia by reviewing the USDA zone info.

Planting Calendar for Bishop's Weed

Frost tolerance for bishop's weed:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant bishop's weed quite a bit earlier in the year because they do well in cold.

The earliest that you can plant bishop's weed in Philadelphia is February. However, you really should wait until March if you don't want to take any chances.

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

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Philadelphia. It might get as low as 0°F during the coldest months of winter.

Remember that USDA zone info for Philadelphia is an average and the actual date of last frost will vary from year to year. Half of the time in Philadelphia you get a frost after April 15 so always be ready to cover your bishop's weed in the event of a late frost.

USDA Zone Info for Philadelphia

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Philadelphia

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