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

A way of figuring out when it's possible to plant pentas is to use the USDA zone info for Romeoville.

Planting Calendar for Pentas

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

You really shouldn't plant pentas until after all chance of frost has passed because they require warm weather.

The earliest that you can plant pentas in Romeoville 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. You probably don't want to wait any later than that or else your pentas may not have a chance to fully mature. Starting your pentas indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Romeoville. In the coldest months of winter you should expect an average low temperature of -15°F.

Keep in mind that USDA zone info for Romeoville is not always accurate and the actual date of last frost changes from year to year. Half of the time in Romeoville there is a last frost after April 15 so always be ready to cover your pentas if you have a surprise late frost.

USDA Zone Info for Romeoville

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Romeoville

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