Manolo Blahnik, the Sex in the City cobbler, and a Hollywood handbag maker are among a clutch of Vogue-favoured designers who will be prancing around the Floral Design Marquee at the Chelsea Flower Show next week. Jane Packer and other celebrity floral designers (flower arrangers no longer exist, apparently) will make displays to set off swanky handbags, silk scarves and stilettos. Suddenly, the flower show has turned into an extension of the Kings Road.

I can't wait to fork out £420 for my rose-embellished silk Manolos - so practical for mulching the marrows. Or slightly more for a Susannah Hunter handbag to carry my tools. Or £260 for a Jo Malone candle to blot out the dreadful stench of fresh flowers.

I've nothing against fashion designers: I just don't want to see them at Chelsea. The show's organiser, the Royal Horticultural Society, justifies the intrusion by saying that they are trying to include the local community. On that basis why not invite representation from Victoria coach station? Or encourage Sloane Square Tube to shunt a flower-graffiti train into the show?

As it is, the local community already involves itself in Chelsea via “Sloane in Bloom”. This encourages chic local shops to deck themselves out for Chelsea Week. It looks wonderful. So why on earth do these swanky fashion-mongers have to teeter into the show itself? Chelsea's site is already so overcrowded that garden designs, and visitor numbers, are restricted.

And it's not as if the show lacks glamour and beauty. Among the attractions that leave me swooning, year after year, are Kelways peonies and David Austin's roses. Integrity is another admirable Chelsea quality. Gnomes are banned on grounds of Good Taste, and all exhibitors are vetted down to the last aphid to make sure they are environmentally and aesthetically sound.

The result is a display of the finest plants and gardens in the world brought together by the Royal Horticultural Society - and while I am not suggesting that everything at the show has to be slavishly horticultural I question the need to fill the grounds with people more concerned with catwalks than catmint.

Until now the catwalk analogy has been used at Chelsea to talk about plants and gardens strutting their stuff. Today, the show's catwalk credentials have shifted so far in favour of fashion that the Bible of such things, Vogue online, has announced that this will be Chelsea's most stylish show ever.

Wrong judge. Wrong criterion. Please, RHS: return Chelsea to garden makers.

Jane Owen is the Times Online gardening expert

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