My ruby red mandevilla vine in L. A. keeps getting yellow leaves all over. It has not flowered yet. It gets about 6-7 hrs of sun now. Is that too much? Why are the leaves turning yellow? Is it too much water?
Yellow Leaves on Mandevilla Plant
Certified GKH Gardening Expert
Mandevilla favor humid conditions. If your plant is exposed to the sun, the soil may be too hot. Try misting/spraying the leaves with water in the mornings and keep the soil moist (NOT wet). You may also want to consider moving your plant (if possible) to an area that doesn't receive direct sunlight for extended periods of time.
Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/vines/mandevilla/mandevilla-plant.htm