In general, a rose is symbolic of love, beauty and/or something of value. Outside of the realm of literature, roses and their colors are symbolic: red roses can symbolize passion, while white roses can symbolize purity.
In literature, while the rose often represents love, its symbolic meaning can take on new depths beyond the silky texture of the flower or its fragrance. The pain often accompanying love, found in the bloom’s thorns, can express the dual nature of love.
To begin, a symbol is defined as...
...anything that represents or stands for something else (natural, conventional, literary)
In Robert Burns' poem "A Red, Red Rose," the poet compares his love to a new red rose, bringing to mind new love—a newness of a relationship, and the delight of romance when everything is fresh and exciting:
O my Luve's like a red, red rose
That's newly sprung in June...
The simile notes that the speaker's love (whether the emotion or the woman) is like a rose that has just bloomed in June. It is not wilted by the heat or turning brown, but is brand new.
In Emily Bronte's "A Little Budding Rose," the poet also compares the rose to love, but to a broken one:
The rose is blasted, withered, blighted,
Its root has felt a worm,
And like a heart beloved and slighted
Failed, faded, shrunk its form.
In Romeo and Juliet, Shakespeare writes, "A rose by any other name would smell so sweet." Juliet speaks of Romeo, the young man she falls in love with so quickly. Their families hate each other, but his name does not define her feelings. Here the rose symbolizes the perfection of love—and the author infers that nothing can disturb the feeling Juliet has for Romeo.
Michael Ferber, author of A Dictionary of Literary Symbols, notes:
The rose blooms in the spring, and does not bloom long...
By comparison, a rose in this circumstance would symbolize love that will not last. As the days pass, the rose opens and soon withers and dies. This is another association with the rose and love.
In William Faulkner's haunting short story, "A Rose For Emily," Miss Emily is never allowed by her father to date: no man is good enough for her. After her father dies, she begins to see Homer Barron, who mysteriously disappears, seeming to leave Miss Emily alone for the remainder of her days. In this case, the rose can symbolize the brief time of love that Miss Emily shared with Barron before he was gone.
The rose is also symbolic of beauty. Ferber also notes that the rose is referred to in Achilles Tatius' novel (2.1)—greatly praised:
If Zeus had wished to give the ﬂowers a king, he would have named the rose, for it is the ornament of the world, the glory of plants, the eye of ﬂowers, the blush of the meadow...the agent of Aphrodite.
The rose may also symbolize something of great value. In Robert Frost's poem "The Rose Family," the poet notes...
The rose is a rose,
And was always a rose...
He then notes that other things are also (we assume, metaphorically) called roses, such as apples and pears. But he goes on to conclude about the person to whom he is writing...
You, of course, are a rose—
But were always a rose.
He notes that while other things may be compared to the rose, the woman he speaks to was never anything but a rose: the implication is that she is all the wonderful things associated with a rose, and very important to him.