One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant nierembergia in Zone 7a should be figured out by using the USDA zone info.

Planting Calendar for Nierembergia

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

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

The earliest that you can plant nierembergia in Zone 7a 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. 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 Zone 7a. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Zone 7a may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 7a you get surprised by a frost after April 15 so make sure that you are ready to cover your nierembergia if you have one of those late frosts.

USDA Zone Info for Zone 7a

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Zone 7a

You may be interested in your other planting guides for Zone 7a.