Answer: There are so many different fragrant roses that I doubt any two people could agree on a list of the ten "most" fragrant. Part of the reason for this is that people's sense of smell differs from person to person, and so one rose may appeal greatly to one person, but seem too msuky or too sweet or too spicy, for example, to someone else.
The other issue would be if you are planning on growing hybrid tea roses or modern landscape roses or so called heirloom roses, or a combination. For your hedge you might look at the very winter hardy and sturdy Rosa rugosa and cultivars of that type of rose, they are probably the hardiest and lowest maintenance roses available -- these roses even resent being sprayed. Hybrid tea roses, on the other hand, will need careful attention throughout the season, skilled pruning each spring, constant deadheading and most likely also require a preventive spray program to stay healthy all summer. They will also need special winter protection to survive your harsh winter weather. So that is something to think about.
What I would suggest you do is identify a list of roses that do especially well in your local area and then select the ones whose fragrance you personally like best from among those. This will give you a head start in growing healthy roses, in addition to assuring you enjoy the fragrance of your special garden.
You could start your research by visiting display gardens with roses and by visiting rose shows -- this is actually a busy rose show season -- and at American Rose Society shows there are usually society members available to consult with gardeners about selecting and growing roses. The ARS also has consulting rosarians available to help gardeners with their specific rose questions. You can find the show schedule as well as local club listings and extensive rose growing information at the ARS web site.
Fragrance in Roses
Many ARS Articles about roses
Ohio State Extension is also a great resource for you.
planting roses - Ohio State Extension
rose care in Ohio -- Ohio State Extension
Your local county extension staff may also have suggestions about roses that do especially well in your local area. They should also be able to help you with the initial soil testing and soil preparation phase based on their knowledge of the local soil with an eye on growing roses.
Best of luck with your new project!
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