When to Plant Periwinkles in Bethlehem, PA

One of the first steps you take when you are figuring out 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.

You can figure out when you can plant periwinkles in Bethlehem by reviewing the USDA zone info.


Planting Calendar for Periwinkles

Frost tolerance for periwinkles: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

Since periwinkles are not cold tolerant it's necessary to wait until after the last frost before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant periwinkles
Possibly ok, but a risky time to plant periwinkles
Probably not a good time to plant periwinkles

The earliest that you can plant periwinkles 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 periwinkles and expect a good harvest is probably August. If you wait any later than that and your periwinkles may not have a chance to really do well. You can get started a little bit earlier by starting your periwinkles indoors.

Last Frost Date

The average date of last frost is April 15 in Bethlehem. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for Bethlehem is just an average 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 make sure that you are ready to protect your periwinkles if you have one of those late frosts.

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 Low0°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.