It's a canna lily, one of the variegated leaf ones. If you "google" images for "variegated leaf canna" you may id the actual cultivar. Sometimes the leaves are more highly regarded than the flowers.
They grow from a rhizome and shoot from a node. Although they are fairly tough, I think yours is doing it too tough.
They will actually grow as a bog plant in sun, or even in pots set in water. While hardy enough in open ground, yours is probably not going to get enough moisture in that sandy loam to actually thrive. Plus the reflected heat from that fence. If you can find it a kinder spot I'm sure you will be rewarded.
In my area because the growing season is the wetter summer season, we have a bit of a problem with rust - i have no proof that it's the same one that affects the plumeria but it seems to go back and forth in my garden and the only solution I've found is to cut off the affected bits and bin then.

Yeah, they are usually pretty tough plants but this one's not looking too good. The soil looks to be mostly sand and the fact that it is heaped up ensures really good - too good - drainage. I'd try replanting it on flatter ground and in a more moisture retentive medium.
B.

Hey there photo is of canna tropicana just in case you haven't been able to identify it yet
Cheers sookika