Seems to me the hydrangea and the hibiscus are poor companions. Hibiscus can't get enough sun and hydranges likes part shade.
Is there enough sun for petunias?
Or perhaps angelonia?
Linda C

I agree with you about where I planted the hibiscus. It's being nurseried until we develop a bed later this year which will be full sun. I needed to put it somewhere, so we compromised! if it doesn't flower this year that's okay, as long as it survives otherwise. Come spring we'll transplant it in its new sunny home.

Petunias are a good idea. I have a lot of them, but they are so cheerful and colorful. Angelonia aren't easy to find around here this late in the year, they seem to sell out quickly.

* Petunias (question whether there's enough sun, though - ? )

* Ageratum

* Geraniums

* Heliotrope

* New Guniea impatiens

* Browallia

* Impatiens

Geraniums and heliotrope and New Guinea do quite nicely in part-shade and you only need a few plants to make an impact.

The browallia and regular impatiens are "bedders" so you'll need more of them to fill in, but both are great choices for part-shade.

Ageratum and petunia would probably prefer more sun, so I'd try those only if you can't find nice shade plants.