Hi Jim: I had no problems getting commercial Gladiolus cultivars to return in zone 7 of southern New Mexico. Over time they would dwindle out but I am not sure it was a winter hardiness issue. In northern Illinois I have a single corm of Gladiolus byzantinus (Gladiolus communis ssp. byzantinus) that has come back for a couple of years. We have some wild collected Gladiolus taxa from Republic of Georgia but the corms (from seed) have not gotten large enough to test them outdoors. Then, of course, we have a bumper crop of chipmunks that seen to prefer bulbs of know wild origin - which is another reason they haven't gone out yet. Boyce Tankersley Director of Living Plant Documentation Chicago Botanic Garden 1000 Lake Cook Road Glencoe, IL 60022 tel: 847-835-6841 fax: 847-835-1635 email: btankers@chicagobotanic.org