The answer to whether raspberry bushes have thorns is generally yes, but with an important botanical distinction. Most of the common raspberry varieties, which belong to the Rubus genus, possess sharp, protective appendages on their canes. These structures serve as an effective defense mechanism for the plant. The presence of these sharp outgrowths is a characteristic that has persisted through the evolution of wild and cultivated raspberries.
The Nature of Raspberry Prickles
The sharp structures found on raspberry canes are technically called “prickles,” not true thorns, a detail that distinguishes their botanical origin. True thorns are modified stems or branches containing vascular tissue, or veins, that connect them deeply to the plant’s core structure. In contrast, raspberry prickles develop only from the outer layers of the stem, specifically the epidermis and cortex, meaning they lack that internal vascular connection.
These prickles are typically smaller and more numerous than true thorns and can be snapped off cleanly from the cane’s surface. They often present as fine, needle-like spines, frequently denser near the base of the cane. Their primary function is protection, deterring herbivores like deer and small mammals from eating the leaves and canes.
Thorny Versus Thornless Varieties
Raspberry cultivars show significant variation in the density and size of their prickles, ranging from heavily armed to completely smooth. Many traditional and wild varieties, such as the popular everbearing ‘Heritage’ raspberry, are notably prickly. These varieties have retained the protective characteristic that aids in their survival and hardiness in various growing conditions.
The development of thornless varieties has made berry harvesting easier for home gardeners and commercial growers. Cultivars like the red raspberry ‘Canby’ are nearly thornless, while others, such as ‘Joan J,’ are genuinely spineless. These plants result from selective breeding aimed at improving ease of handling. However, thornless types may have different growing needs, such as less winter hardiness, compared to their prickly counterparts.
Safe Handling and Pruning
Pruning thorny raspberry canes requires specific precautions to prevent painful scratches and potential injury. Wearing heavy-duty leather gloves is highly recommended, as standard gardening gloves are often not thick enough to block the sharp prickles. Long sleeves and durable pants should also be worn to protect the arms and legs from contact with the dense growth.
Pruning techniques focus on removing spent canes to encourage new growth and maintain plant health while minimizing contact with the sharp surfaces. For summer-bearing varieties, the old, two-year-old canes (floricanes) should be cut down to the ground after fruiting. Thinning the new, one-year-old canes (primocanes) to a spacing of about six inches apart allows for better air circulation and light penetration.