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 determine when it's possible to plant calliopsis in Williamsport by referring to the USDA zone info.

Planting Calendar for Calliopsis

Frost tolerance for calliopsis:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Calliopsis do not do well in cold weather which means that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant calliopsis in Williamsport 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 calliopsis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your calliopsis may not have a chance to fully mature. You can get started a little bit earlier by starting your calliopsis indoors.

Last Frost Date

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

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Williamsport and it will vary from year to year. Half of the time in Williamsport you get a frost after April 15 so be sure to be ready to cover your calliopsis if you have a late frost.

USDA Zone Info for Williamsport

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 Williamsport

You may be interested in your other planting guides for Williamsport.