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.

By referring to the USDA zone info for Harrisburg it's a good idea to estimate when it's a good idea to plant portulaca.

Planting Calendar for Portulaca

Frost tolerance for portulaca:	Not tolerant of frost.
When to plant:	After the last frost.

It's a bad idea to plant portulaca until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant portulaca 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 portulaca and expect a good harvest is probably August. If you wait any later than that and your portulaca may not have a chance to grow to maturity. If you are starting your portulaca indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Harrisburg. In the coldest months of winter you can expect an average low temperature of 5°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Harrisburg and it can change quite a bit from year to year. Since half of the time in Harrisburg there is a last frost after April 15 be ready to cover your portulaca if you have a surprise 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.