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Aquatic Group

The Aquatic Group contains cultivars that thrive as marginal water plants. Characteristically, they will have lance-shaped foliage and long, thin rhizomes, which help provide anchorage in a moving environment. Having been derived from Canna glauca or Canna flaccida, they will have inherited their lance-shaped foliage and long, thin rhizomes.

A side-effect of the long, thin rhizomes is that they are not able to store large amounts of starch, and cannot tolerate the horticultural ‘trick’ of stopping rhizome growth over the winter months, so that rhizomes can be stored away from the destructive cold and frost. Instead, Aquatic Group cultivars must be kept growing over the cold winter months, although they will tolerate a low-level of watering during that period.


The first cultivars bred specifically for their aquatic abilities were introduced by Dr Richard Armstrong, firstly in his role as geneticist at Longwood Gardens and later in a private capacity when he retired to Hawaii.



Canna ‘Severn’

The Longwood aquatic cannas were bred for large ponds and lakes, but look out of scale with normal garden small ponds, and so the River Series of aquatic cannas was bred specifically to fill that gap, all being under 1 metre in height.


See also: Canna Cultivar Groups