Greenfly on sweet peas
 

I had a bad infestation (on sweet peas) so I drenched them in soapy water. The greenfly were washed away, but now the plants look scaly and yellowy-white. The flower stems are very short and the buds tiny and tight. Some have dropped off. A week later now, I have drenched them with fresh water to get the soap out. They look no different. Should I just cut off all the flower stems to make new ones grow? No flowers have come yet on any of the plants but we are late here anyway. I just have all tight buds.