Answer: Some roses put on only one display of flowers each year; other varieties are repeat bloomers. If your roses bloom only once, in the early summer, they are probably the kinds that will not repeat the blooming cycle and there's nothing you can do to encourage additional bloom.
Roses bloom best when planted in a site that receives full day sunshine. If your rose is a repeat-bloomer but isn't repeating the floral display all summer long, it probably needs more sunshine than it is receiving.
Best wishes with your roses!
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