This large and fast growing dahlia likes full to half sun with a well draining soil. hardy down to 0C, possibly a full degrees further with a good mulch.
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Hedychium coccineum var. aurantiacum
This superb ginger likes full to half sun with well draining soils, hardy down to -5C it may take a few more degrees of frost but would not like to risk it! In winter bring into a frost free environment until spring,