One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Philadelphia can be looked at to figure out when to plant doronicum.

Planting Calendar for Doronicum

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

You can plant doronicum a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant doronicum 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 doronicum and expect a good harvest is probably September. Any later than that and your doronicum may not have a chance to fully mature. You can get started a little bit earlier by starting your doronicum indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Philadelphia. In the coldest months of winter you should expect an average low temperature of 0°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Philadelphia and it changes from year to year. Half of the time in Philadelphia it frosts late in the year after April 15 so just be sure to be ready to cover your doronicum 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.