One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when it's possible to plant erysimum by checking out the USDA zone info for Harrisburg.

Planting Calendar for Erysimum

Frost tolerance for erysimum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Erysimum can survive in moderate cold which tells us that you can plant them a little bit earlier in the year than other frost tender plants.

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

The last month that you can plant erysimum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your erysimum may not have a chance to fully mature. You can get started a few weeks earlier by starting your erysimum indoors.

Last Frost Date

In Harrisburg the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 0°F.

Since the USDA zone info for Harrisburg is not always accurate the actual date of last frost will vary from year to year. Half of the time in Harrisburg you get a frost after April 15 so just be sure to be ready to cover your erysimum in the event of one of those late frosts.

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.