Posted: 13/01/2016 at 19:00
Hello photosynthesize. Size matters. (With the right size pot for the plant and feeding you can grow countless plants but weight is an issue on roof terraces.) I trust you have checked roots are not pot bound, infested with grubs or in smelly, wet growing medium. So.. What else could it be?
Wind shear (the compass direction and the angle the wind strikes) effects water uptake and leaf scorch which will damage or stunt growth.( IKEA sell pretty, taped balcony railing sheets and canopies to offer wind, rain and sun protection.) Are there any heating vents, boiler exhausts or air conditioning vents causing huge temperature variations?