Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant nierembergia in Carbondale can be determined by referring to the USDA zone info.

Planting Calendar for Nierembergia

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

Since nierembergia are not cold tolerant it is necessary to wait until after the last frost has passed before you can plant them.

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

Last Frost Date

On average all chance of frost has passed is on April 15 in Carbondale. In the coldest months of winter you should expect an average low temperature of -15°F.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Carbondale and it will vary from year to year. Since half of the time in Carbondale you get a frost after April 15 be ready to protect your nierembergia in the event of a surprise late frost.

USDA Zone Info for Carbondale

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 Carbondale

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