One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can determine when it's a good idea to plant tritoma in Philadelphia by checking out the USDA zone info.

Planting Calendar for Tritoma

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

You can plant tritoma earlier in the year because they do well in cold.

The earliest that you can plant tritoma 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 tritoma and expect a good harvest is probably September. Any later than that and your tritoma may not have a chance to really do well. Starting your tritoma indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Philadelphia. It might get as low as 0°F during the coldest months of winter.

Always 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 can change quite a bit from year to year. Half of the time in Philadelphia last frost occurs after April 15 so always be ready to protect your tritoma in the event of 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.