Butch mentions overspray but doesn't place much emphasis on it. Seems that most growers who've been around a while have used foliar fertilization to help growth. However most quickly learn that the downsides are large - at least aesthetically and often outweigh the benefits. I remember spraying a tray of VFTs a number of years ago. I ended up with a nasty green gelatinous mess. Once it started - it kept growing - no matter what I did. It was the gift that kept on giving.... The 'things' in CP soil are accustomed to a deprived environment - when they get a burst of nutrients - it's party time!!
Do you have any special methods to avoid the above nastiness when root feeding?