Accused triple murderer Erin Patterson will return to the witness box after telling a jury she foraged wild mushrooms in the lead up to serving poisonous beef Wellingtons.

She will return today for a third day as a defence witness.

Patterson has pleaded not guilty to three murders and one attempted murder over the July 2023 lunch she served to her former in-laws, Don and Gail Patterson, 70, and Gail’s sister Heather Wilkinson, 66.

All three died in hospital days after eating the meals. Patterson maintains the poisonings were not deliberate.

The sole survivor of the lunch was Heather’s husband Ian Wilkinson, who has attended court most days since giving evidence in week two of the trial.

He sat silently at the back of the courtroom yesterday as Patterson explained she had begun foraging for wild mushrooms during the COVID-19 pandemic in 2020.

Before the end of the day, defence barrister Colin Mandy SC asked Patterson “do you accept there must have been death cap mushrooms” in the lunch she served to her former husband’s family.

“Yes I do,” she told a full courtroom and 14 jurors.

She said she started cooking wild mushrooms in the years before the lunch, and “ate it and then saw what happened”.

“They tasted good and I didn’t get sick,” she said.

Patterson said she would forage for mushrooms at Korumburra Botanic Gardens, on her three-acre properties in Korumburra and Leongatha, and along a rail trail leading out of Leongatha.

She said she bought a food dehydrator to begin drying mushrooms because she liked eating them but “it’s a very small season” and she wanted to preserve them.

Patterson was shown photos of mushrooms in a dehydrator and said she’d picked them from Korumburra gardens and dehydrated them whole as “a bit of an experiment”.

“They were still a bit mushy inside,” she said.

“They just didn’t dry properly.”

She said she would dehydrate mushrooms from Woolworths and wild-picked mushrooms and put them in containers in her pantry.