Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant napa valley fern in Philadelphia should be determined by reviewing the USDA zone info.

Planting Calendar for Napa Valley Fern

Frost tolerance for napa valley fern:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's probably not a good idea to plant napa valley fern until after the last frost because they do not do well in cold weather.

The earliest that you can plant napa valley fern in Philadelphia is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant napa valley fern and expect a good harvest is probably August. If you wait any later than that and your napa valley fern may not have a chance to really do well. You can get started a few weeks earlier by starting your napa valley fern indoors.

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.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Philadelphia and it will vary from year to year. Half of the time in Philadelphia there is a last frost after March 15 so always be ready to protect your napa valley fern 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.