One of the first steps you take when you are estimating your gardening schedule is find your 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.

A common way of figuring out when you can plant hemerocallis is to look at the USDA zone info for Philadelphia.

Planting Calendar for Hemerocallis

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

Since hemerocallis do well in moderate cold you can plant them just a bit earlier in the year than other frost tender 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 really do well. If you are starting your hemerocallis indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Philadelphia the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

Remember that USDA zone info for Philadelphia is an average and the actual date of last frost changes from year to year. Since half of the time in Philadelphia you get surprised by a frost after March 15 be ready to protect your hemerocallis if you have a late frost.

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.