Q.why are the healthy, green leaves falling off in mass on my 4 O’clock potted plant?
I’ve had this potted plant for several months now; it’s healthy, beautiful, and vining everywhere! All of a sudden, in the past two days, most of the leaves have fallen off! They are healthy, firm, green and just detached! the stems and blooms are healthy, firm and beautiful. Any ideas?

Certified GKH Gardening Expert
They will start to decline about this time of year in most places. Don't worry, though. These will come back next year.
This article will give you more information on the care of this plant: https://www.gardeningknowhow.com/ornamental/flowers/four-oclocks/four-oclock-plants.htm