Q.Impatiens
My Impatiens were blooming beautifully but now they are dropping leaves from the lower stems. They look very sparse. Cannot see any insects. They have had enough water. What could be the problem?
Certified GKH Gardening Expert
Your plants may be affected by a fungus or spider mites. White flecks or webbing on the underside of the leaves are good indications of spider mites. The leaves of impatiens will begin to look gray or bronze in color as more damage is done. A heavy infestation will cause leaves to die and drop off. You can use neem oil to kill spider mites and relieve any fungal issues as well. Here is additional information that may be helpful: https://www.gardeningknowhow.com/ornamental/flowers/impatiens/impatiens-problems.htm
https://www.gardeningknowhow.com/problems/pests/neem-oil-uses.htm