The USDA Zone info is a great tool for gardeners to help us determine 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.

In Harrisburg you can estimate when to plant nierembergia 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 has passed.

It's probably not a good idea to plant nierembergia until after the last frost when the weather gets warmer because they require warm weather.

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 grow to maturity. If you are starting your nierembergia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Harrisburg. You should expect an average low temperature of 0°F in the coldest months of winter.

It's important to remember that USDA zone info for Harrisburg is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Harrisburg you get surprised by a frost after April 15 be ready to cover your nierembergia in the event of a surprise 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.