These are host plants of the Mottled Emigrant and Plain Tiger butterflies.
The former is the Senna alata (synonym: Cassia alata) and even though I have seen it before, I am still not sure if this is a normal or mildly variegated specimen. Perhaps someone can enlighten me about this.
The latter is the Calotropis gigantea that I posted recently. I found the remnant pupal case of the very beautiful butterfly hanging on the underside of a leaf.
And where are these plants found? Head straight to the Hospital in the North and you will have all the answers.