Columbia Giant Thornless Blackberry is a recent introduction from Oregon State University and the USDA that brings the best of Pacific Northwest breeding to home gardens across zones 6-9. Unlike thorny blackberry varieties, this trailing cultivar produces abundantly without the prickly stems that make harvesting a chore. Expect early summer harvests of substantial yields, with plants reaching about 6 feet tall and thriving in full sun. Its thornless canes and vigorous growth habit, combined with proven hardiness across many regions, make it a standout choice for gardeners seeking a productive berry plant that's actually pleasant to maintain.
Full Sun
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6-9
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This Oregon State University selection ripens early in summer, typically by early July in the Pacific Northwest, with each crown producing 10-15 pounds of berries. The trailing, vigorous growth pattern means you'll need trellis support to manage the canes effectively, but that's a small investment for such generous yields. The thornless stems are a game-changer for harvesters who've battled scratched arms and torn clothes with traditional blackberry varieties.
Fresh eating is the primary use for Columbia Giant Thornless blackberries, thanks to early-season ripening that provides berries when spring transitions to summer. The substantial yields from each plant also make this variety worthwhile for preserving, whether through freezing, jam-making, or other preparations that capture the season's bounty.
No timeline data available yet for this variety.
Plant bare-root or potted Columbia Giant Thornless canes in early spring or fall, spacing them at least 3-4 feet apart to allow for their vigorous, trailing growth. Position the crown just at or slightly below soil level. Set up trellis support at planting time rather than waiting, since the young canes will quickly begin their enthusiastic climb.
Begin harvesting in early July in the Pacific Northwest and slightly later in other regions within zones 6-9. Pick berries when they're fully black and slightly soft to the touch, yielding gently to show they've fully ripened. Each crown should produce 10-15 pounds of berries during the season, so plan multiple picking sessions as fruit ripens over several weeks.
Prune Columbia Giant Thornless after harvest in late summer, removing old floricanes that produced fruit that season and thinning out weak or crowded canes. Train the vigorous new primocanes onto trellis supports throughout the growing season, tying them horizontally or at angles to encourage branching and even fruit distribution. Head back excessively long canes in late winter if needed to maintain your preferred plant size and shape.
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“Columbia Giant Thornless Blackberry emerged from collaborative breeding work between Oregon State University and the USDA, representing modern horticultural science aimed at making blackberry cultivation more accessible and rewarding. The variety was specifically developed to thrive in the challenging Pacific Northwest climate while eliminating one of the primary frustrations home gardeners face with blackberries: the relentless thorns. This new introduction carries the genetic foundation of decades of blackberry improvement, bringing university-tested vigor and productivity to gardeners nationwide.”