One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

It's a good idea to figure out when it's possible to plant regal geranium by using the USDA zone info for Harrisburg.

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.

You can plant regal geranium a bit earlier in the year because they do ok in moderate cold.

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. You probably don't want to wait any later than that or else your regal geranium may not have a chance to grow to maturity. If you are starting your regal geranium indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

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

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Harrisburg and it is different every year. Since half of the time in Harrisburg there is a last frost after April 15 be ready to protect your regal geranium if you have a late frost.

USDA Zone Info for Harrisburg

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°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 0°F.

Plants to Grow in Harrisburg

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