The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Alexandria you can determine when it's a good idea to plant nierembergia by looking at 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 are not cold tolerant you really should wait until after the last frost has passed before you can plant them.

The earliest that you can plant nierembergia in Alexandria 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 fully mature. 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 all chance of frost has passed is on May 15 in Alexandria. You can expect an average low temperature of -30°F in the coldest months of winter.

Always keep in mind that USDA zone info for Alexandria is just an average and the actual date of last frost is different every year. Half of the time in Alexandria you get surprised by a frost after May 15 so just be sure to be ready to protect your nierembergia in the event of one of those late frosts.

USDA Zone Info for Alexandria

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 Alexandria

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