The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant hemerocallis in Philadelphia by using the USDA zone info.

Planting Calendar for Hemerocallis

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

Hemerocallis can survive in a little bit of cold which means that you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant hemerocallis 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 hemerocallis and expect a good harvest is probably September. If you wait any later than that and your hemerocallis may not have a chance to fully mature. If you are starting your hemerocallis indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Philadelphia the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Philadelphia is just an average the actual date of last frost will vary from year to year. Since half of the time in Philadelphia last frost occurs after April 15 be ready to cover your hemerocallis 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.