When to Plant Dianthus in Philadelphia, PA

Before planting it is a good idea to find your USDA Zone info to determine 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 first opportunity to plant dianthus in Philadelphia should be figured out by reviewing the USDA zone info.


Planting Calendar for Dianthus

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

Since dianthus are moderately cold tolerant you can plant them a little bit earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant dianthus
Possibly ok, but a risky time to plant dianthus
Probably not a good time to plant dianthus

The earliest that you can plant dianthus 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 dianthus and expect a good harvest is probably September. If you wait any later than that and your dianthus may not have a chance to really do well. Starting your dianthus indoors is a great way to get them started a few 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.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Philadelphia and it changes from year to year. Half of the time in Philadelphia you get a frost after April 15 so make sure that you are ready to cover your dianthus 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 Low0°F
Highest Expected Low5°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.