I have three or four different types of Thunbergia and NONE have bloomed for me yet - too darned hot!

I have the regular yellow Thunbergia planted on the east side of our apartment building. A friend has hers(an orange variety)planted on the south side. My friend's has stopped blooming, and mine, although late to start blooming, is going gangbusters right now. I give a very dilute miracle-gro solution occasionally, water regularly, and that's about it. I was surprised as I thought they preferred full sun and heat.
I would go ahead and try the bloom booster...what have you got to lose at this point? Maybe it will surprise you at the end of the season. If you get any more blooms at all be sure to save the seed for next year. You have to catch the seed pod as soon as it turns brown, or it will pop open and you'll lose the seed.

Up here in Calgary, Alberta, Canada, our thunbergia blooms only when the nights are no less than 50 degrees. Anything colder than that, and they get grumpy. We've had a chilly summer, so the thunbergia isn't blooming as well as it should be.

I've always grown it in full sun to part shade. I know someone here who grows it in full shade, and it blooms for her too. Maybe if you are in a hot climate, you can try it in the shade. Normally, it is covered in thousands of blooms, all summer long. It's very floriferous!

Hi I am in zone 8 a

it bloomed for a while in the beginning but now only a few scattered blooms

I will have to try a different fertilizer

I have been using miracle grow

I have purchased both yellow and orange blossom both this year and last. I never can get the orange to blossom, yet the yellow's blossom profusely. Same Soil, same amount of sun, water, fertilizer etc. So frustrating as the orange never get a bloom. What to do? Next year, only buying the yellow