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

One way of determining when it's the best time to plant celeriac is to consult the USDA zone info for Philadelphia.

Planting Calendar for Celeriac

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

Celeriac are moderately cold tolerant which means that you can plant them earlier than more sensitive plants.

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

Last Frost Date

On average the last frost has passed is on March 15 in Philadelphia. It might get as low as 10°F during the coldest months of winter.

Remember that USDA zone info for Philadelphia is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Philadelphia last frost occurs after March 15 so always be ready to protect your celeriac in the event of one of those late frosts.

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.