I suggest the manufacturer and ask them these questions. Could it not be some growing condition or disease that is damaging your roots. As I have not used roundup around this species I can't comment. However I have used the product on /around every temperate garden flower known to man. Every species of temperate Iris, hybrids (thousands) and thousands of hybrid daylily varieties without problem, including every temperate cut flower! No problems. For roundup to get into the plant it cannot travel through soil. It must enter the pores on healthy leaves and pores on some nonwoody stems. I find that many times the user doesn't follow the directions on the label. Do you think Monsanto would risk millions in fines producing a chemical that harmed plants people want to grow. I am truly sorry you had a crop failure but I do not believe the cause was the roundup. If you spray between flowers and weeds you have to prevent the spray from drifting on your flowers. It is non selective in what it kills. Please remember there are a lot of diseases- viral, fungal and bacterial that can easily damage or weaken plants. Russ H. In a message dated 4/2/2013 1:21:27 A.M. Pacific Daylight Time, bulborum@gmail.com writes: Hi Russ Nice article I don't agree that Round up is harmless after one week one of my suppliers used it three months before seeding Mirabilis jalapa the harvest was less as half from normal and the quality from the harvested roots was terrible I stopped selling them because they started rotting on my stand in September so whatever they say some way round up doesn't break down completely and is also infecting probably roots or the just emerging cotyledon Roland It turns into a harmless nontoxic chemical. R de Boer La Maugardiere 1 F 27260 EPAIGNES FRANCE Phone./Fax 0033-232-576-204 Email: bulborum@gmail.com Facebook: https://facebook.com/pages/Bulborum/… _______________________________________________ pbs mailing list pbs@lists.ibiblio.org http://pacificbulbsociety.org/list.php http://pacificbulbsociety.org/pbswiki/