Zone 7 is at the low end of zones recommended for night blooming jasmine. That means keeping night blooming jasmine alive and healthy in zone 7 can be a little more difficult than in other zones. One alternative to keeping this plant outdoors is to grow it in a pot and bring it in for the winter. However, night blooming jasmine is very fragrant and growing it indoors may not be desirable.
Plant your night blooming jasmine next to your house, if possible. Heat from the house will increase the temperature of the air and soil in adjacent beds.
Mulch your jasmine with 4 to 6 inches of straw, dry leaves or other organic mulch that has a high air content. Mulches with high air content act as a better insulator than compacted mulches.
Staple clear plastic sheeting over the jasmine as a tent between your house and the ground. Place rocks on the ground to secure the plastic. The clear plastic will act as a temporary greenhouse and will help trap heat from the side of your house to keep the jasmine warmer during unexpected cold periods.
If you expect a sudden, unseasonably cold period, consider placing a stock pot full of hot water under the plastic. The heat and steam will help keep the area under the plastic warmer than normal.