Hi Fay, welcome to ATP. Sorry you are having problems with your weigela.
You say it gets watered daily by a misting system. It would seem to me that the leaves would be getting wet, but perhaps not the roots. When you transplant a shrub from container to ground, it is necessary for the plant's root system to receive adequate water and that is generally achieved by either regular rainfall or hand watering/irrigation that provides about 1 inch of water a week.
You say there are trees nearby, and they are notorious for using up as much water as is available to them. They may be soaking up what water is being put down for your shrub. I would recommend moving a bit of soil around your shrub and checking it for moisture 3 to 4 inches below the surface.. It is also possible that the mister is wetting the leaves and they are scalding in the sun.
It would be very useful if you could post pictures of the plant, its' surrounding plantings and a close-up of the leaves themselves.
