Great air flow & drainage make it almost impossible to over water or "wet feet". The roots will have the air circulation they need. The soil does not fall out of the sides or bottoms. Wide Lip More Flexibility to Fit & Reusable: 4.2" extra wide lip design on top makes it easy to fit & keep it in place & lends more flexibility to the hole-saw you use, as you don't have to be as precise with your hole cutting.
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