Ready to Wear: Paper bag headwear is masterminded by Philip Treacy. Tesco won’t cut it

If the look of the summer was fashionably deshabille and even crumpled, as spearheaded by Prada, then autumn's catwalks take this one step further.

At Alexander McQueen there are bin-liner dresses and paper bag hats. Giles Deacon's overblown eveningwear appears to have had broken glass thrown at it. The look may be described as post-apocalyptic, perhaps (this particular apocalypse being the current economic climate) or even as trash couture. Either way, however informed by detritus each collection may be, they are far from low-budget and it almost goes without saying, it is utterly futile to try this at home.

A garment that may indeed be referencing the aforementioned refuse sacks, for example, is actually crafted in paper nylon exclusively created for the designer in question. The paper bag headwear is masterminded by milliner Philip Treacy and any number of try-outs with the Tesco variety will simply not, well, not cut it. Giles Deacon's smashed surface embellishment, similarly, is actually crystal and while his collection might borrow from the uniform of punk – in spirit at least – it too is executed with an attention to detail and pattern-cutting expertise that is normally the preserve of made-to-measure clothing as opposed to mere ready-to-wear.

A more watered-down interpretation of a similar theme can be seen elsewhere in the designer collections in the form of clothing that looks toughened – all that studded leather – but is, in reality, entirely luxe. It's all just an illusion, the high end masquerading as something rather more rough-edged (very rough-edged) in flavour and that is as profound a statement as any given the economic black hole that the fashion industry faces just now.

No such irony – or indeed illusory – qualities are likely to be on display at high street level. Topshop Unique's collection will be lapped up by all who like their T-shirts crafted in string and with stringy old jackets to match. For anyone too young to remember rave culture the first time around this is an entirely legitimate and suitably simple make-do-and-mend fashion statement. All those longer in the tooth, however, could be forgiven for preferring their wardrobe didn't bring The Tribe (if you don't know, don't ask) to mind.

Back to Prada again where a distinctly Land Girls mood invaded yet another seminal collection that has so far attracted as many column inches for accessories as beautiful clothing. The first lady of fashion's first foray into waders may be just the thing when we're all up to our waists in water what with global warming, one might not unreasonably think. Except, of course, that these boots are not made for survival in flood conditions – they're leather, you see. Another witty ruse, then, on the part of one of this century's most inspired and inspiring designers.