Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant gayfeather in Philadelphia can be figured out by reviewing the USDA zone info.

Planting Calendar for Gayfeather

Frost tolerance for gayfeather:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Gayfeather tend to make it in a bit of cold which tells us that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant gayfeather 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 gayfeather and expect a good harvest is probably September. You probably don't want to wait any later than that or else your gayfeather may not have a chance to grow to maturity. If you are starting your gayfeather indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Philadelphia. It might get as low as 10°F during the coldest months of winter.

Since the USDA zone info for Philadelphia is just an average the actual date of last frost is different every year. Since half of the time in Philadelphia there is a last frost after March 15 be ready to cover your gayfeather if you have a surprise 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.