One of the best tools that you have as gardeners to help us determine 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.

In Roanoke you can figure out 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 all chance of frost has passed.

Nierembergia require warm weather which means that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant nierembergia in Roanoke 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. If you wait any later than that and your nierembergia may not have a chance to really do well. Starting your nierembergia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Roanoke. In the coldest months of winter you should expect an average low temperature of 5°F.

It's important to remember that USDA zone info for Roanoke is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Roanoke last frost occurs after April 15 so make sure that you are ready to protect your nierembergia if you have one of those late frosts.

USDA Zone Info for Roanoke

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 Roanoke

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