One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 to plant calliopsis by looking at the USDA zone info for Bethlehem.

Planting Calendar for Calliopsis

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

Since calliopsis require warm weather it is important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant calliopsis in Bethlehem 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

The average date of last frost is April 15 in Bethlehem. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Bethlehem is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Bethlehem there is a last frost after April 15 so be sure to be ready to protect your calliopsis if you have a late frost.

USDA Zone Info for Bethlehem

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 Bethlehem

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