i have a goji berry plant the looks healthy all over except for the new growth on the top part which stopped growing and wilted. i keep this plant indoors for the winter and it stays under a artificial light for fourteen hours. this plant is also next to a window. i keep it planted in a small pot with 1/4 sand 3/4 peat moss and some worm castings. i water this plant only when the top part of the soil feels bone dry. one day when the sun was shining through the window from outside and was touching the top of the plant for the first time the top part of the plant wilted. when i pulled the plant away from the sun it totally recovered top and all. the next day the whole plant slightly wilted and the top part wilted a lot and so i felt the soil and it was dry so i watered the plant. the plant recovered totally but the top part still looked wilted. i need help to figure out what is wrong with the plant, i sent some pictures of the plant so that it is easier to understand.
