Catweazle: The Battle of the Giants 1970 s2e11

The Catweazle series from 1970

S2.E11 ∙ The Battle of the Giants Sun, Mar 21, 1971

Poorly Catweazle's remedy potion gets mixed up with Groome's
marrow fertiliser; the result is Cedric's is bigger than both
Groome's and his dad's, so earning him an Aquarian prize to
donate to Catweazle's collection.