Buds Falling Off Hibiscus Plant

Hi! Your hibiscus may have a nutrient deficiency or overload, too much or too little water, could also be a soil pH issue, or an insect pest. I would bet your problem is nutrient deficiency or soil pH problem. What kind of soil is it potted in (where did you get it? if bought was it 'potting mix', general use, or maybe a specific use medium?) and do you fertilize it at all? If so, with what and how often? Lastly, how much sun does it get per day and how often do you water?