thanks all for appreciation...
brig sb before growing these from seeds my opinion and experience was same as yours but now i am very much impressed with their performance.these are medium sized plants of almost 2 feet high...flower size is big and they bloom periodically in summers..i sowed seeds in march and they started blooming in june and are still blooming.and they multiply very fast..

all credit goes to imran khuram sb i got idea of growing these from seeds after watching his beautiful cannas...and still waiting for canna president and cleopatra from his side....hahahhah
@izhar bhai according to my experience only red is small in size other are full size flowers almost 4 inches..thanks for good advise when to use dap.can i use now.?