Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Roswell you can estimate when it's a good idea to plant nierembergia 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 need to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant nierembergia in Roswell 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 grow to maturity. Starting your nierembergia indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Roswell. In the coldest months of winter you can expect an average low temperature of 5°F.

Since the USDA zone info for Roswell is just an average the actual date of last frost is different every year. Since half of the time in Roswell last frost occurs after April 15 be ready to cover your nierembergia in the event of one of those late frosts.

USDA Zone Info for Roswell

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Roswell

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