When to Plant Pentas in Allentown, PA

The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Allentown you should be able to estimate when it's a good idea to plant pentas.


Planting Calendar for Pentas

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

Pentas are not cold tolerant which tells us that it's necessary to wait until it warms up after the last frost before you can plant them.

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

The earliest that you can plant pentas in Allentown 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 pentas and expect a good harvest is probably August. Any later than that and your pentas may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your pentas indoors.

Last Frost Date

The average date of last frost is April 15 in Allentown. In the coldest months of winter you can expect an average low temperature of -5°F.

Since the USDA zone info for Allentown is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Allentown you get a frost after April 15 so always be ready to protect your pentas in the event of a late frost.

USDA Zone Info for Allentown

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 Allentown

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