Common causes of downward roll:
-insufficient root space
-overapplication of nitrogen
-insufficient ventilation
Less common, but definitely possible when combined with other visible symptoms:
-pH out of range

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stinkyattic Reviewed by stinkyattic on . "Canoe" leaves rolling downward?.......Need some quick help Ebb & Flow set up. Gh nutes...... What causes leaves to give a "canoe" look downward? Like the leaves "Roll" downward almost like you would roll a phatty......I think it's either to much water or not enough.....please correct me if Im wrong. No pics avail.... Thanks in advance Rating: 5