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.

You can figure out when you can plant nierembergia in Harrisburg by checking out the USDA zone info.

Planting Calendar for Nierembergia

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

Nierembergia do not do well in cold weather which means that you have to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant nierembergia in Harrisburg 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 nierembergia and expect a good harvest is probably August. If you wait any later than that and your nierembergia may not have a chance to really do well. You can get started a little bit earlier by starting your nierembergia indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Harrisburg. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for Harrisburg is just an average the actual date of last frost changes from year to year. Since half of the time in Harrisburg you get a frost after April 15 be ready to protect your nierembergia 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.