Garden Detective: Bringing back a butterfly bush

A swallowtail butterfly takes in the nectar of a butterfly bush. (July 22, 2007) Credit: Newsday / Michael E. Ach
Leave it be. The new growth is encouraging, and it probably will be just fine. In March 2014, cut it to within a foot of ground level. Good luck!
In the meantime, stay tuned: I will be offering my suggestions for suitable impatiens alternatives in a column next month.

Impatiens just starting to yellow and curl their leaves downwards. There is sporulation of downy mildew on the undersurface of the leaves that doesn't show. Credit: Handout
You also might create a diversion: Heat equal parts jelly and water in a saucepan and stir until it becomes syrupy. Allow to cool and pour to fill a jar, then set the jar in a distant part of the yard. The gnats, along with some other pests, will be drawn to the jar and, hopefully, away from your picnic.