I have experimented with reticulata Iris a great deal. I wash the (clay) pots every year, and dust with Bordeaux Mixture (sulfur) when repotting and also use dolomitic lime. I discard the spent potting compost - not near my frames! I do grow and flower them from seed, the best controls I have found for Ink Spot is good hygiene and stable growing conditions. I find the best way to introduce Ink spot is to stress the plants in the last stage of growth and early dormancy with erratic temperatures and moisture levels. This fits with Rolands advice. It is a lottery as to whether an individual pot will have suffered from the disease but I can normally produce clean pots of all the commercial varieties I have ever managed to obtain, as well as the wild forms. I am skeptical that cutting the bulbs would remove the disease, Brian Mathew in "The Iris" regards an infected bulb as incurable. However infected bulbs will yield pristine bulbils which will grow on into healthy bulbs. I know there are others here who know more about fungal infections than I, but I do believe to discard the sclerota, if that is the right term, is not to remove an infection. Peter (UK) On Sun, Nov 6, 2011 at 8:32 PM, Rodger Whitlock <totototo@telus.net> wrote: > If you are raising reticulata irises from seed (and hence have absolutely > clean > plants), it would be a advisable to completely refrain from bringing > commercial > forms into your garden. > > If commercial reticulata irises are irresistible but you don't want to > introduce ink spot into your garden, you may wish to try eliminating it > from > newly purchased stock. Peel the tunics off the bulbs. Carefully examine > each > bulb and using a new single-edged razor blade, cut out any lesions you > find.Dust > the wounds with sulfur. Plant the bulbs in new soil in a clean pot and > grow on > in the normal way. > > Be careful that the tunics you remove, and slivers of bulb you have cut > out, > the razor blade you use, and the soil you have grown them in (for just one > year) all go into the garbage, not the compost. Clean the pots with liquid > chlorine bleach before re-use. >