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 should be able to determine when to plant creeping zinnia by using the USDA zone info for Harrisburg.

Planting Calendar for Creeping Zinnia

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

Creeping Zinnia tend to make it in a tiny bit of cold which means that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant creeping zinnia 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 creeping zinnia and expect a good harvest is probably August. Any later than that and your creeping zinnia may not have a chance to fully mature. Starting your creeping zinnia indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Harrisburg may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Harrisburg you get a frost after April 15 so be sure to be ready to cover your creeping zinnia in the event of one of those late frosts.

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.