Thanks, Bob. That is a good way to tell. Most of mine have crawled just under the soil surface, maybe leaving just the very top of the rhizome exposed. The majority of the rhizome substance digs itself in well. I suspect that is because my late-summer to fall season is quite hot and sunshine is strong. I am in a strong wind season right now; and the soil in raised beds is always at risk of blowing. When I add mulch to the roses in spring, I'll probably also give a bit to the irises that have had their soil blown away. Robt R Pries wrote: > ... Look at the plants you have > that have been in place for a year or two. The Iris > will push itself deeper or crawl further out of the > ground according to its own sense of conditions. Your > established plants can tell you exactly where a new > plant should go. Most rhizomatous Irises have the top > of the rhizome exposed to some degree. I like to > consult with my plants before I make decisions. > Bob Pries, on a cold ozark High Ridge, just soth of St > Louis. > >