ITV host Alan Titchmarsh found the mushrooms while filming a special to air Christmas Day. The mushroom -- Amanita muscaria, or fly agaric -- is a hallucinogenic mushroom and grows wild.
"That depends what you mean. It's eaten in some cultures for its hallucinogenic affects. But it also makes people who eat it very sick," said ecology expert Mick Crawley on the Christmas special. "The old-fashioned thing to do was to feed it to the village idiot, then drink his urine because you get all of the high without any of the sickness."
"There are several hundred fungi species in the palace garden, including a small number of naturally occurring fly agaric mushrooms," said a spokesman for Buckingham Palace, adding the fungi are helpful in retaining nutrients.
The palace press office confirmed that none of the wild mushrooms in the garden are served in the palace meals.