I just took this a pic at pinterest because there isn't any sweet potato growing nearby (I live in a surbuban area and these things can occasionally be tossed in empty lots and grow wild for free picking, we don't have seasons, only rain or sunshine being near the equator so this one grows all year round). Not a potato expert but your soil probably helped a lot. The leaves are bigger while the ones I know of are more angulated and smaller than the image on this comment. Hopefully they taste just as delicious too (if they do differ in variety from. The ones grown in southeast Asia). Good luck and take care!
Thats awesome they grow all year around where you live. We grow them from spring to fall here and then restart next spring.
Those leaves do look a little different than mine, so maybe its a different cultivar.
What color are the spuds? Mine are red on the outside and yellow on the inside.
Hah I am sure they will taste good, I have eaten alot of the leaves raw and seems just like some stringy lettuce to me.