Cassia Alata is not a Florida native Cassia, but it is a great host plant for sulphur butterflies.

There are lots of different kinds of Cassia plants. I don't have them all, but all of the ones that I do have are on the Cassia page this link takes you to.

The yellow blooms stick up like candles, so I presume that's how this plant got its common name. The green things sticking out under the flowers are seed pods. They'll turn a dark brown and split open to spill their seeds when they mature.

Cassia Alata is also a nectar plant; check out the skipper butterfly sipping from the flower in the photograph below (I think it's a Monk Skipper. It has a very long proboscis!)