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.

The USDA zone info for Philadelphia can be reviewed to estimate when it's possible to plant foxglove.

Planting Calendar for Foxglove

Frost tolerance for foxglove:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Foxglove do well in moderate cold which tells us that you can get them planted earlier than more sensitive plants.

The earliest that you can plant foxglove 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 foxglove and expect a good harvest is probably September. You probably don't want to wait any later than that or else your foxglove may not have a chance to fully mature. Starting your foxglove indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Philadelphia. You should expect an average low temperature of 0°F in the coldest months of winter.

Keep in mind that USDA zone info for Philadelphia is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Philadelphia it frosts late in the year after April 15 be ready to protect your foxglove in the event of a surprise 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.