One of the first steps you take when you are getting a good idea 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.

In Harper Woods you can estimate when to plant nierembergia by referring to the USDA zone info.

Planting Calendar for Nierembergia

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

Since nierembergia require warm weather you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant nierembergia in Harper Woods 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 couple of weeks earlier by starting your nierembergia indoors.

Last Frost Date

In Harper Woods the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Harper Woods and it is different every year. Half of the time in Harper Woods you get a frost after April 15 so always be ready to cover your nierembergia if you have a late frost.

USDA Zone Info for Harper Woods

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 Low	0°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 Harper Woods

You may be interested in your other planting guides for Harper Woods.