One of the best tools that you have as gardeners to help us estimate 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 estimate when you can plant argyranthemum in Philadelphia by reviewing the USDA zone info.

Planting Calendar for Argyranthemum

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

Argyranthemum require warm weather which tells us that it is important to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant argyranthemum 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 argyranthemum and expect a good harvest is probably August. Any later than that and your argyranthemum may not have a chance to fully mature. If you are starting your argyranthemum 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. You can expect an average low temperature of 0°F in the coldest months of winter.

It's important to remember that USDA zone info for Philadelphia is an average and the actual date of last frost changes from year to year. Half of the time in Philadelphia you get a frost after April 15 so make sure that you are prepared to cover your argyranthemum if you have a 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.