Experts and BHG readers answer.
few leaves on roses
Did your rose bushes have more leaves that have now fallen off, or have they always been sparse? If there have never been many leaves, it may be an indication that the plants need more sun. If the leaves develop but fall off, several factors could be involved. Black spot is a fungal disease that attacks many roses in humid climates. The leaves develop black or gray irregular spots, and the leaves turn yellow before dropping off. To control the black spot fungus, spray the roses with fungicide throughout the growing season. Or remove these susceptible roses and replant with varieties that are resistant to black spot. If the leaves just turn yellow before dropping off it could be an insect infestation (such as mites or thrips). A forceful spray of water may dislodge mites, but you may also have to spray with an insecticide to manage them.