Judge Kristina Montgomery QC ruled Lucy Fox will be subject to a hospital order after a jury unanimously agreed that she stabbed her mother, Judith Fox, to death last year.
The remains of Mrs Fox, known as Judy, were found in July 2020, a month after she went missing.
Lucy Fox was tried in her absence at Stafford Crown Court after the judge heard she was unfit to stand trial and was “not fit to participate in the trial in any meaningful way” due to her mental health.
However, after the jury found she committed murder and arson with intent to endanger life - for setting fire to a doormat at the home occupied by her brother and his family - the judge said a trial could happen in future.
"It may be that in future a trial to assess her full criminal culpability could take place," the judge said.
However, she added that unless the trial took place it was important "the public is protected from Lucy Fox", who she said had a paranoid illness "consistent with a finding of paranoid schizophrenia".
During the trial jurors heard how the 39-year-old of Bernard’s Hill, Bridgnorth, killed her mother because she was upset their family home in Shifnal was being sold and her belongings would be going into storage.
Mrs Fox, who had been a company at the Shropshire Star and Express & Star for 13 years, was killed between June 12 and 14 last year.
Her remains were eventually discovered in woodland next to the River Severn near Ironbridge, the following month after an extensive police search.
Lucy Fox also starting a fire at her brother's home in Apley Park.
Police found a makeshift device consisting of two aerosol cans wrapped in tape with her palm and fingerprints.
Judge Montgomery also praised members of the Fox family who have been in attendance throughout, and said she would read their victim impact statements with sympathy and in private.
"I have no doubt and can only imagine the devastation wreaked on her family and how awful it must be for them to sit through the trial and hear the the details of what happened to Mrs Fox.
"I pay tribute to them," the judge said.
She also praised the jury - which was only required to determine whether or not she committed the acts, and not to bring in verdicts of guilty - for its service in the case which she described as "harrowing case for everybody".