One of the first steps you take when you are figuring out 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.

The USDA zone info for Harrisburg can be reffered to in order to determine when it's possible to plant dianthus.

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 one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant dianthus in Harrisburg 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. Any later than that and your dianthus may not have a chance to really do well. You can get started a little bit earlier by starting your dianthus indoors.

Last Frost Date

The average date of last frost is April 15 in Harrisburg. You can expect an average low temperature of 5°F in the coldest months of winter.

Since the USDA zone info for Harrisburg is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Harrisburg you get surprised by a frost after April 15 so make sure that you are ready to protect your dianthus if you have a late frost.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Harrisburg

You may be interested in your other planting guides for Harrisburg.