One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when to plant nierembergia by checking out the USDA zone info for Devils Lake.

Planting Calendar for Nierembergia

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

Since nierembergia do not do well in cold weather you need to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant nierembergia in Devils Lake is May. However, you really should wait until June 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. Any later than that and your nierembergia may not have a chance to grow to maturity. If you are starting your nierembergia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on May 15 in Devils Lake. In the coldest months of winter you can expect an average low temperature of -30°F.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Devils Lake and it is different every year. Half of the time in Devils Lake you get surprised by a frost after May 15 so just be sure to be ready to cover your nierembergia if you have one of those late frosts.

USDA Zone Info for Devils Lake

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Devils Lake

You may be interested in your other planting guides for Devils Lake.