One of the best tools that you have as gardeners to help us determine 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.

You can figure out when to plant flowering kale in Philadelphia by using the USDA zone info.

Planting Calendar for Flowering Kale

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

Flowering Kale do well in moderate cold which means that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant flowering 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 flowering kale and expect a good harvest is probably September. Any later than that and your flowering kale may not have a chance to really do well. You can get started a couple of weeks earlier by starting your flowering kale indoors.

Last Frost Date

On average the last frost has passed is on March 15 in Philadelphia. You can expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Philadelphia may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Philadelphia it frosts late in the year after March 15 be ready to protect your flowering kale if you have a 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.