Roses can bloom for a fair amount of time. . .
But if I want them blooming at the beginning and at the end of the story -- and it's not over winter -- the question is how modern I can make them. Old-style roses were once a season. Mind you, they produced enormous bursts of blossom during that time, a lot more than ever blooming roses did, but only a burst, and by staggering types I could give the bushes quite a period of bloom as long as it moved from bush to bush. Not so long as new style. . . which officially and firmly started in 1867. Solidly in the Victorian era, and the tech I've got does not match. (Since that was the introduction of Hybrid Teas, based on stock brought back from China, the technology really does matter.)
Mind you there's magic about. Could substitute for the tea trade.
Or, for that matter, could prolong the blossoming season.
And at that, I'm not even sure how long the heroine is away. The on-stage action takes up a handful of days, but I explicitly talk about her travels and her weariness from the length of them. . . .
juggle, juggle, juggle. . . .