This is the second winter for this plant. I'm in the Midwest, Illinois. The first year it flourished outdoors. We brought it in for the winter. It did well, no flowers but great green leaves. We returned it outdoors spring 2016. It never seemed to do as well as the first year. It flowered but not nearly as much nor did the flowers sustain long. Now we entered our winter, we brought it in way before any frost and it seemed to go into a shock. The leaves are scarce, the yellowing isn't as much as when we brought it in. (But leaves were yellowing a lot outdoors too this year.) The puzzling part is it continues to flower, one at a time and it hangs on. I'm thinking I need to cut it back but I'm happy to find you for professional advice. It is in a south facing window. Thank you greatly.
Certified GKH Gardening Expert
Hibiscus leaves commonly turn yellowish when the plant is under various types of stress, and it's usually nothing to worry about:
Indoors, giving the plant as much light as possible and only watering when needed will increase the likelihood of the plant maintaining green leaves, but in any case, it should recover in the spring. Pruning back your hibiscus by up to 1/3 of its size can also help it put out healthier growth: