One of the best tools that you have as gardeners to help us figure out 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.

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

Planting Calendar for Daylily

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

Daylily do well in moderate cold which tells us that you can plant them earlier than other plants that might not handle the cold.

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

Last Frost Date

The average date of last frost is March 15 in Philadelphia. You should expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Philadelphia is not always accurate the actual date of last frost changes from year to year. Since half of the time in Philadelphia it frosts late in the year after March 15 be ready to cover your daylily in the event of 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.