Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant nierembergia in Caledonia should be estimated by looking at the USDA zone info.

Planting Calendar for Nierembergia

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

You really shouldn't plant nierembergia until after the last frost because they require warm weather.

The earliest that you can plant nierembergia in Caledonia 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. If you wait any later than that and your nierembergia may not have a chance to fully mature. You can get started a few weeks earlier by starting your nierembergia indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Caledonia. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Caledonia is just an average and the actual date of last frost changes from year to year. Half of the time in Caledonia you get surprised by a frost after April 15 so be sure to be ready to cover your nierembergia in the event of a surprise late frost.

USDA Zone Info for Caledonia

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 Caledonia

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