20L - 32cm H x 28cm W x 28cm D. 25L - 33cm H x 30cm W x 30cm D. 30L - 35cm H x 32.5cm W x 32.5cm D. Air pruning the roots; when roots hit the inside wall of a traditional plastic pot, they'll simply turn in the most convenient direction and keep growing, causing circling and tangling.
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