What Is the Purpose of a Thorn on a Rose Bush?

Roses have long been revered for their beauty and fragrance. Historically, they were considered religious symbols, although in the early Middle Ages they were frowned upon as a symbol of Roman excess and debauchery. The thorns, while unpleasant to gardeners, serve a practical purpose. They guarantee that roses survive the wiles of humans and animals.

Religious Symbolism

During the middle ages, roses were thought to have significant religious meaning. A red rose symbolized martyrdom or the blood of Christ. Thorn-less roses signified a sinless life while roses with thorns represented flawed mortality. St. Dorothea at the Cloisters was, according to Columbia University, "condemned to death by the Emperor Diocletian for refusing to marry." The emperor's secretary Theophilus taunted her as she approached her execution, asking her to send him a bouquet of roses from heaven. At Dorothea's death, (in midwinter) a child brought the secretary a bouquet of white, thorn-less roses. He instantly converted and was later martyred.

Historical Meaning

Roses with thorns have long been a symbol of adversity, as well as sacrifice. Abraham Lincoln said, "We can complain because rose bushes have thorns, or rejoice because thorn bushes have roses." In Oscar Wilde's famous work, "The Nightingale and the Rose," a nightingale pierces its breast on a rose thorn so the lover may have a red rose for his beloved.

Practical Purposes

The growths on roses are technically prickles, not thorns. Thorns are hard woody outgrowths of branches, such as cactus and trees, according to the American Rose Society, while prickles are soft growths. Roses evolved with prickles as a protective adaptation. Rose prickles may curve downward to prevent animals from climbing and eating them. Other members of the Rosacea family, such as blackberries and raspberries, also have prickles.

Warnings

Rose prickles may seem harmless, but have been known to cause serious infections. Sporotrichosis occurs when fungus on the rose thorn enters a victim's blood stream. The first symptoms appear within three weeks of contact. Small lumps on the skin become open sores. As the infection travels through the body it can cause joint paint and swelling and even lung or central nervous system damage. The elderly and those with immune system disorders are most at risk.

Thornless Varieties

The elderly and gardeners with children should consider thorn-less varieties, as well as anyone who loves roses, but hates prickles. Some varieties to try include Mme. Legras de St. Germain, Mme. Plantier, Zéphirine Drouhin and Tausendschön.