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 will be able to figure out when it's the best time to plant nierembergia by looking at the USDA zone info for Moorhead.

Planting Calendar for Nierembergia

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

Nierembergia do not do well in cold weather which tells us that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant nierembergia in Moorhead 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. If you wait 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 Moorhead. In the coldest months of winter you can expect an average low temperature of -30°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Moorhead and it will vary from year to year. Since half of the time in Moorhead you get a frost after May 15 be ready to cover your nierembergia in the event of one of those late frosts.

USDA Zone Info for Moorhead

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 Moorhead

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