maybe you arent watering it enough? I am not a pro I just learn everything by experience, But I have had a Hibiscus for 2 years now, and I find that if I get lazy on the watering then the leaves will yellow, it seems to need a lot of water. I give mine lots of water 2 days a week. But mine is huge so I don't know if yours needs that much.

Yellowing of the leaves can be a nutritional deficiency, consider how long your plant has been in the pot, it may need some fresh new potting mix.

Yellowing can also mean too much water, stick your finger in the mix and see if its wet, before you water.

Is it difficult to grow hibiscus in your part of the world ? Keeping it inside may be a problem, does it get enough sun ?

Having buds is good.

Popi

Hi I'm new to this page, my first message.
I have obvious;y been over watering my Hibiscus Tree. What is the best way to put required nutrients back into the soil. I live in Barcelona and it is difficult to get many of the usual feeds here.
Ann