This is one of the several caudiciform Impatiens I have right now - it may be Impatiens mirabilis or something closely related to it. The inflorescence is sequentially flowering and the caudex fist size and corky. I am not sure how large it can grow but a true I. mirabilis is of tree-like proportion. Many new caudiciform Impatiens are being discovered in this part the world as I speak and this could well be one of the new discoveries - I am including more pics here with the hope of someone suggesting an ID one day.
Generally caudiciform Impatiens are difficult - some of them just die without rhyme or reason. This species seems easier than others, it even produced a crop of viable seedlings for me !