James Peppiatt, 21, is accused of stabbing to death 55-year-old Tony Eastlake during an altercation near to his popular flower stall in Essex Road.
Peppiatt, the son of Mr Eastlake’s late partner, was charged with murder in early June and appeared at the Old Bailey on Monday via videolink from HMP Belmarsh.
He spoke to confirm his name before entering a not guilty plea to the charge.
Jonas Milner, defending, had told an earlier hearing that Peppiatt was due to contest the allegation at trial.
“Mr Peppiatt is aged 21, he is charged with the murder of Tony Eastlake, who was aged 55,” said prosecutor Julian Evans.
“Mr Eastlake died from a single stab wound to his back, in the area of Halliford St, N1 on May 29 this year.
“Mr Eastlake was a florist who worked in a flower store opposite Essex Road station for about 40 years. He was a very well-known member of the local community.
“He separated from his wife in around 2018 and in due course began a relationship with Alicia Callaghan, the defendant’s mother.”
Ms Callaghan, 43, took her own life on April 1 this year at her Islington home.
Hundreds of people attended a vigil for Mr Eastlake at his flower stand, Florence & Fleur, two days after his death. The florist had worked in the trade since he was 14-years-old, earning the nickname the “Flower Man of Islington”.
Peppiatt, from Islington, has been remanded in custody until trial which is due to start on July 18 next year.