Mine does that also. It'll usually grow only about one or two blooms at a time and then they fall off the next day. Don't worry! :)

They bloom on new growth so the more new growth, soil warmth, and light, the more flowers you can potentially get at one time.

How big is the pot? I have mine (which is going on 10 years old now and which is about the same "height" as yours, but not trained as a standard), in a 14", which is about the largest that I can lug in and out. There were originally 4 young babies all potted together through several transplants to reach that size pot. Last year, there was so much rain that 2 of my 4 potted together, actually died leaving 2 remaining. The remaining 2 have been busy taking up that space and I really need to either prune it all back, repot larger, or go through some combination of root and top pruning (too lazy at the moment to do all that).

But when they get going, I can often have 7 - 8 flowers open on it a day (and they close the next day):

{{gwi:724}}

I would recommend if you repot that you make sure your soil has good drainage. You could add some bark chunks in (alot of people are heralding the greatness of coconut husk chips too). I top dress with bark chips too to keep the soil moist as they can be thirsty plants if they are outside in the sun and warmth.

Jenny, do you know the name of your hibiscus? I love the colors. Also, is your hibiscus growing from the balcony, and hanging over the edge? It looks cool.

Lynne - it is an "Edward LaPlante", bought at my local Home Depot about 10 years ago. It originally came as 4 babies in a 1 gallon pot and I've progressively potted them up over the years (now in a 14"). I never pruned them and let them weep over like that, sortof like how I saw tropical hibs growing along a river in Kauai. LOL Seems to like it as this gives the branches a few extra hours of sun as it goes up over the top of my building. I put the container on a little white plastic table and position the branches up over the rail where they can get a breeze and get rained on. Of course it is a bit of a nuisance to bring in but I have a usual spot for it inside where it can sprawl across one of those plastic 3-drawer shelf units that I have near the balcony door.

Here's the flower:

I loved the hot pink/orange combo. I really had to hunt on the web to ID it but luckily I had found a site awhile ago (which is here) that had info and descriptions of all types of hibs and I saw another website where someone won a local hibiscus society show award for their bloom of this. The flowers are smaller than other tropical hibs but that makes it nice for containerizing.