Different Roses Signify Many Different Things
Here are some helpful definitions :

A rose in general
Love, Beauty
A leaf of roses
"There is hope. Stick to it!"
A twig of roses
Annoyance
A thorn of roses
"Every cloud has a silver lining."
A white rose
Innocence, Freedom, Simplicity,
A bud of white roses
Chastity
A withered white rose
A vow of love throughout one's life
A small white rose
"You are too young for love."
A red rose
"I love you.", Passion, Beauty, Exemplariness
A bud of red roses
Purity, "I do good to you."
A leaf of red roses
Pure beauty, "I wish your happiness."
A scarlet rose
Passionate love, Romance, Conspiracy,
A crimson rose
"I am dying for loving you."
A deep crimson rose
Shame
A dark red rose
"I'll bear you a grudge to the last breath."
A pink rose
A beautiful girl
A large-flowered pink rose
"I am pregnant."
A yellow rose
"I love you.", Friendship, "I got tired of love.", Unchastity, Jealousy, "Let us part friends."
A midle-sized yellow rose
"You are insincere."
A small yellow rose
"Let us part friends, not in anger."
Red and white roses together
A warm heart, Unity
A multiple-petaled rose
Pride, "Don't laugh at me."
A single-petaled rose
Pure spiritual love, Respect
A thornless rose
Sincerity and friendship
A bud of thornless roses
Naivete, Innocence,
Three buds and one rose in full bloom
 "Keep it a secret forever."
One bud and two roses in full bloom
"Keep it a secret for the present."
A rose in full bloom
"I'm a married woman."
A wild rose
A tender heart .