The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Harrisburg it's a good idea to figure out when it's a good idea to plant regal geranium.

Planting Calendar for Regal Geranium

Frost tolerance for regal geranium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since regal geranium do ok in moderate cold you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant regal geranium in Harrisburg is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant regal geranium and expect a good harvest is probably August. If you wait any later than that and your regal geranium may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your regal geranium indoors.

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. It might get as low as 0°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Harrisburg and it can change quite a bit from year to year. Since half of the time in Harrisburg it frosts late in the year after April 15 be ready to protect your regal geranium in the event of a late frost.

USDA Zone Info for Harrisburg

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 Harrisburg

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