>From a nurseryman's standpoint, "drench" is a thorough soaking of the plant, including the media it's in. And just to get technical, I sometimes use a large tray (in this case one of those "under the bed" plastic storage boxes without the lid to put all the plants in I'm going to drench. This technique would be used where there were root beasties and where you need an exposure of the pesticide of 30 seconds to the roots to be sure to kill them. Robin Hansen Coastal southwest Oregon, Zone 9