Urban gardener, Cleve West: One vindaloo shrub to go please

Garden designers, as opposed to botanists, are not so easy to please when it comes to unusual plants. It's not that we don't get excited about something different or extraordinary, it's Chelsea just that we usually want them gold medal to do more than merely rely on winner 2006 their oddity value to make a contribution to a garden.

For plant collectors, however, the more unusual, rare or remote a plant the better. A three-week hike through bandit-infested mountains with poisonous creatures lurking at every corner is enough to bestow upon a plant due reverence. But just occasionally designers, who spend most of their time worrying about space, form, volume and mass, are beguiled by a plant of scarcity when they least expect it.

My horticultural eureka moment came in the few months before the Chelsea Flower Show last year when, on a visit to Jekka's Herb Farm, I fell in love with a number of relatively unusual shrubs noted for their drought tolerance. Two rosemaries were given plenty of pre-show publicity - the South African variety, Eriocephalus africanus and Westringia fruticosa ' Variegata' from Australia. So too was Ozothamnus hookeri, not least because it dispelled the myth that designers are somewhat sniffy when it comes to variegation. But the shrub that made the biggest impression on me was Escallonia resinosa.

It's not an obvious star and I assumed it would play a supporting role to some of the more showy plants, but the inclement weather that made Chelsea 2006 one of the wettest and coldest on record, helped it perform way beyond the call of duty by smelling of ... curry.

It's much more subtle than Helichrysum italicum, which is quite crude by comparison, and ephemeral to a point where you doubt the sanity of your own nose. Squeeze a leaf, stem or root of the escallonia and you'll get nothing. Walk casually by after a rain shower, however, and the confusing, delightful pungency will begin to work its magic. It's as if all the leaves have the minutest trace that, with a little help from evaporation after a downpour, is just enough to scent the most delicate of clouds. But then your olfactory senses are bamboozled when the aroma disappears just as you think you are tuning in to its source.

A native of Peru and Chile, the shrub is salt resistant and very hardy. The Incas used timber from it for their buildings. Angus White at Architectural Plants tells me that it is gaining popularity as a quick-growing hedge. 'It has a curious, disorganised habit with curled leaves that resemble the Cork Oak ( Quercus suber), making the whole thing look like a 1970s hairstyle. A bit messy left to its own devices.' He then suggested, in a rather endearing way, that it might be the perfect plant for the likes of me (and himself, he hastily added to soften the blow), who simply cannot exist without a little chaos scratching at the window-panes.

I didn't tell him I had just such a hairstyle (a Kevin Keegan, wasn't it?) in the Eighties (courtesy of my mother who had a brief spell owning a hairdressing salon; being a live-in guinea-pig was par for the course) as I was distracted by the rare admission from White of selling a shrub that has flowers - an unusual thing in his nursery where foliage, form and the sculptural potential of a plant take precedence over any bloom. 'The fact it's evergreen, with red stems, white flowers and can be clipped into a small tree is obviously useful,' he said. 'But the extra mystery surrounding the curry smell improves its kudos no end.'

Higher humidity or extremes of temperature could be the trigger to set off the smell. The reaction from the public at the Chelsea Flower Show suggests that the olfactory systems of individuals were either quite varied in their sensitivity, or more sensitive at certain times. Either way, it certainly caught their imagination and while there was more than one occasion where I wished people would focus a little more on the rest of the garden instead of a scruffy looking shrub, I must admit to spending a slightly excessive amount of time at the top of Main Avenue with eyes shut and nose in the air, hoping someone would bring me a samosa.