It is a British television institution, famous for its bubbly presenters, resident menagerie and guides on how to make almost anything out of old washing-up bottles and sticky- backed plastic. But a former editor of Blue Peter has said the BBC is trying to kill the programme off.

Biddy Baxter, who edited the show for almost a quarter of a century and oversaw its golden age during the 1970s, has accused the programme's producers of purposefully letting the show go to seed in the hope that it will be decommissioned.

The 74-year-old also said the BBC is planning to ditch many of the tried-and-tested formulas which have made the programme appeal to generations of children, such as the involvement of animals and the making of crafts.

She said: "What I gather is [the programme-makers] don't want to bother with the garden or makes or cooking. They don't want to do animals. It is wrong to discard areas of enormous interest to pre-pubescent children.

"It almost seems they are letting it go pear-shaped on purpose, so they can say it doesn't work. It seems they want it to go out with a whimper, not a bang."

Ms Baxter's comments come at a time when the show's producers are busy putting the final touches to the new series, which is due to start on 23 September. The show celebrates its 50th anniversary on 16 October but its former editor says she has become so disillusioned with the programme that she seldom watches it any more.

One of the BBC's longest-running and most iconic programmes, Blue Peter has entertained and educated millions of the nation's children since it was first launched in 1958. But recently the show's popularity has appeared to be on the wane, with average viewing figures during the previous series dipping below 500,000.

Last year, the show was at the centre of a scandal after it emerged that producers had persuaded a young child to pose as the winner of a phone-in competition to cover up for a technical fault.

The BBC was fined £50,000 by the television industry regulators, Ofcom, which they were forced to pay using money from the licence fee. The debacle also prompted the resignation of the show's editor, Richard Marsden, an event which Ms Baxter described as "a terrible tragedy".

She also expressed concern about the loss of two of the programme's three presenters – Zöe Salmon and Gethin Jones – at the end of the previous series. The changes mean that the show has brought in an entirely new presenting team in the space of two years, making Ms Baxter worry that the constantly changing line-up will damage the show's continuity with younger viewers.

One replacement has already been found in the shape of 25-year-old Helen Skelton, formerly of Newsround but the identity of the third member of the team remains a mystery. The pair will join Blue Peter's only remaining presenter, Andy Akinwolere, who arrived in 2006.

But a spokeswoman for the BBC said: "It's simply not fair to suggest the BBC does not care passionately about Blue Peter. For the past 50 years, the show has been the cornerstone of children's programming in this country... the future for Blue Peter in our eyes is strong and healthy."