The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant kale in Philadelphia should be determined by using the USDA zone info.

Planting Calendar for Kale

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

Since kale are one of those plants that can tolerate a little bit of cold weather you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant kale 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 kale and expect a good harvest is probably September. If you wait any later than that and your kale may not have a chance to fully mature. If you are starting your kale indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Philadelphia the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Philadelphia and it is different every year. Half of the time in Philadelphia you get a frost after April 15 so make sure that you are prepared to protect your kale if you have a surprise 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.