Hi Linda: Here in continental zone 5 the foliage (cultivars and hybrids) does not start to grow until spring. Once temperatures warm sufficiently the rate at which the foliage shoots up is phenomenal. They do not like summer wet and absolutely will not tolerate foot traffic when dormant. Once temperatures start to get hot and the soils start to dry they all promptly go dormant. Both E. robustus and stenophyllus have seedlings coming up around them. 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: firstname.lastname@example.org Seems folly for me to try them in my zone 3. My soil is clay and dry parched silt as a top layer. We are near desert conditions here. Eremurus should love it! My downfall will be the Chinooks I think.