
Raspberries (Rubus idaeus), a bramble fruit, grow in dense, thorny thickets, but regular pruning keeps them neat and contained. Most raspberry bushes have thorns, but a few cultivated varieties are thornless. Hardiness varies by cultivar and goes from U.S. Department of Agriculture plant hardiness zones 4 through 9.
Raspberry Canes
Raspberries are a member of the Rosaceae, or climbed, plant family. Like roses, most raspberries have sharp thorns on their canes. Raspberry shrubs are similar than blackberries, but rather than the sole, sharp thorns on blackberry canes, raspberry thorns tend to be denser creating a “fuzzy” appearance. Though “fuzzy,” the thorns are sharp. Wear gloves and eye protection when pruning or harvesting in the raspberry patch to avoid injury.
Raspberry Plant Characteristics
Growing between two and 9 feet tall, depending on the variety, raspberry shrubs provide delicious fruits in the summer. The plants are biennial, producing canes that bear fruit in the second year. Delicate white or pale pink flowers blossom in spring, followed by berries in summer and into autumn. The particular harvest time varies among varieties. Raspberries grow well in full sun and slightly acidic soil. Dwarf varieties can be grown in pots or hanging planters.
Thornless Cultivars
Horticulturalists breed plants for certain characteristics. Most raspberry varieties grown specifically for a massive fruit harvest have thorns, but if you’d like a more friendly tree, choose a thornless selection. “Raspberry Shortcake” is a thornless dwarf variety that grows 2 to 3 feet tall and produces edible berries. The more standard 4- to 6-foot-tall “Canby Red” cultivar has canes that are almost thornless.
Growing Raspberries
When planting strawberries, place them in the dirt to ensure that the base of the stalks and the crown is just 1 inch below the soil line. Space multiple plants three to four feet apart. Prune in late winter to eliminate all of the canes that produced fruit the season before. These previous canes won’t produce fruit again. Employ a balanced 10-10-10 fertilizer in spring. Use fertilizers as directed on the package label.