Tropical Zone Gardening: Plant ID again , please!, 1 by balaitalisai

balaitalisai wrote:
Here's the second...the yellow and orange flowering plants around another plumeria tree. I've seen these plants often in hanging pots.
On the ground, they easily spread and can be quite a refreshing sight when in bloom...which is morning till 10 a.m. After that, the flowers simply close up. They are very easy to propagate, just cut the top and insert into the soil.

What's their scientific name?