Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to determine when it's possible to plant nierembergia by using the USDA zone info for Purcellville.

Planting Calendar for Nierembergia

Frost tolerance for nierembergia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

You should not plant nierembergia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant nierembergia in Purcellville 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. If you are starting your nierembergia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Purcellville. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Purcellville is just an average the actual date of last frost is different every year. Half of the time in Purcellville there is a last frost after April 15 so always be ready to cover your nierembergia in the event of a late frost.

USDA Zone Info for Purcellville

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 Purcellville

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