In Victoria, BC, Canada, Mermaid starts flowering later than many roses but then flowers continuously till November
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In his garden in Tyler, Texas, Mark Chamblee, of Chamblee's Rose Nursery, grows 'Belinda's Dream', 'Marie Daly', 'Marie Pavie', 'Livin' Easy', 'Easy Going', 'Knockout', and 'Mermaid'. Mark likes these varieties because "they have great hardiness and disease resistance, they are low maintenance and are very free blooming."
An unusual use for 'Mermaid' which may not have occurred to you before -- received via email: This rose is very useful as a vandal deterrent. I live in an inner city cottage and I not infrequently had my letterbox mugged and my picket fence ravaged. My peonies were picked and my sunflowers stripped of their heads. Now 'Mermaid' sprawls and twines through the agapanthus blue pickets delighting the eye, scenting the street and wounding the unworthy. We plan more such organic deterrents round the windows and doors.
Further comment, at Government House in Victoria BC Canada we had a 'Mermaid' growing over a section of glaciated bed rock. The old method of growing roses over rock continues here with screws set in the rock and wires to tie the roses down to. In its first summer 'Mermaid' went from 18 inches to 15 feet. The result of good soil, adequate water and the heat from the rock. Victoria is on the climatic edge for 'Mermaid', is does not do well in Vancouver BC. Government House also has Rosa bracteata, a 'Mermaid' parent, which is even more effective as a vandal deterrent.