GARDENING / Wild plant hunter: In Garden Plant Heritage Week Michael Leapman meets a man who goes to the greatest heights in his enthusiasm for making new plant discoveries

WE ALL know that babies come from gooseberry bushes, but where do gooseberry bushes come from? It seldom occurs to us to ask - and that is why the National Council for the Conservation of Plants and Gardens has a tricky problem in marketing its Garden Plant Heritage Week.

The week began yesterday but you would not be alone if both it and the NCCPG has until now escaped your attention. 'Conservation' and 'heritage' can be chilling words, redolent of do-goodery, inviting a quick turn of the page to something less demanding.

The council (patron: the Prince of Wales) has been going for 15 years and this is its sixth Garden Plant Heritage Week. Heather Harrison, co-ordinator of the week's events, admits that as an institution it is 'gathering momentum rather slowly'. Each year the NCCPG chooses a region of the world and turns the spotlight on plants that originate there, aiming to arouse interest in their conservation. This year it is the turn of the Himalayas.

The most significant group of Himalayan plants grown in Britain are rhododendrons, which flourish on slopes below 10,000ft. They have been popular since Victorian times (though occasionally derided for their bulk, blowsiness and invasive habit) and occur in most of our great show gardens where the soil is acid enough to sustain them.

Many of the finest collections are in the hill country in the north of England and Scotland, which approximates most closely to their native habitat. In the south, a magnificent place to see them is the 160-acre Sir Harold Hillier Gardens and Arboretum near Romsey in Hampshire, where next Sunday the curator, Barry Phillips, will lead a walk themed on the Himalayas as part of Plant Heritage Week (details below).

When I visited him there 10 days ago, the weather was doing its best to mimic a Himalayan winter, with a biting northerly wind defying the evidence of our eyes that we were well into spring. The cold weather has meant that some rhododendrons that would normally have been in full spate were only just beginning to flower but by next Sunday many will be at their showy peak. So will the splendid magnolias, although most of these come from east of the Himalayas.

Phillips, at 44, is already a veteran plant hunter who spent five months on a Himalayan expedition more than 20 years ago, travelling overland from Kew and returning with several new discoveries. He is passionate about the importance of plant heritage.

'It makes people aware of the need to conserve plants,' he says. 'So much has been destroyed in the wild, even in the Himalayas. When I went there we were collecting live plants but you can't do that nowadays. All you can do now is collect seed and you have to get express permission from the host country to do it. That awareness is down to the plant conservation movement and it's a good thing.

'It comes back to the conservation not just of rare Asian plants but of the plants around us. We're losing plants in Britain because people are destroying hedgerows.'

We happened to be passing a marvellous drift of primroses which, unless the weather warms up dramatically, will still look splendid next Sunday. He gestured towards them: 'You don't see so many masses of primroses like this as we did 30 years ago.

'The message will be that everyone can play their part in conservation. At the Hillier Gardens we have 187 plants that are classed as rare and unusual, but if you plant a paper-bark maple, say, in your garden you'd be doing your bit. In the wild, people are cutting them down.'

While the conservation of wildlife is today a popular and respectable cause, plant hunters still labour under a slightly dotty image. We class them with butterfly hunters, frothing with excitement over some apparently insignificant forest flower. We wonder if it is all an excuse for trips to exotic parts of the world.

Not if you care about the variety of plants grown in Britain. One of the first things visitors to the Hillier Gardens see is a splendid Betula utilis, a birch with pink, paper-like bark. It was collected by Roy Lancaster, the television gardening expert who was the first curator of the Hillier Gardens when they were taken over by Hampshire County Council in 1977. Lancaster found it on an expedition to China in 1971 - the first such trip since the great era of plant collecting came to an end in the Thirties. Farther on is another magnificent Himalayan birch, the Betula Jermyns, planted in 1953. At 70ft, it is the tallest of its kind in Britain and one of the oldest.

Apart from the rhododendrons, the other Himalayan plant at its best just now is the pieris, offering double value: its leaves are turning a rich red, as a background to the bunches of tumbling white flowers. Phillips's own favourites are the bamboos, which, clustered in a hollow by a stream, come close, he says, to replicating Himalayan landscape.

He talks enthusiastically about his own plant hunting, which has taken him to Europe, Asia, Latin America and the Caribbean.

'My favourite find was a lovely blue poppy, Meconopsis horridula, which I found at 15,000ft in the Himalayas in 1973. It's called horridula because it's covered in spines to protect it from goats. And on the same trip I found a new species, a lovely bladder campion.

'When I spent six weeks in the Andes in 1986 I discovered the first red gentian and a giant red poppy: it looked like a buttercup but was red and the size of a magnolia. And when I worked for the government in Bermuda I saved the Bermuda Cedar from extinction. It was an important tree - used for housing and boat-building - but 95 per cent of them were wiped out by a scale insect in the 1940s. It took me five years to find a successful method of taking cuttings but I then took 8,000 and they're rooting like mustard and cress.'

And next? 'I'm going to Mongolia in the summer. It's been closed for years. We haven't a clue what we'll find there.

'About a quarter of the plants in an average British garden have probably come from Asian expeditions. There's still new stuff being found and in China there are still unexplored areas. Plants that have been lost are being rediscovered or better examples found. That's what makes it so exciting.'

We reached the warmth of the tea room. 'Sorry if I've talked a lot,' he said. 'People tell me if I hadn't been a gardener I'd have made a good vicar.' Saving souls instead of plants.

Sir Harold Hillier Gardens and Arboretum, Jermyns Lane, Ampfield, Romsey, Hants (0794 68787). Open 10.30-6pm. Admission pounds 3. Barry Phillips's Himalayan-themed walk is at 2pm on Sunday 1 May. Other guided walks for Plant Heritage Week: Today and Sunday 1 May, 2.30pm: Greenbank, Clarkston, Glasgow. Tue 26 April, 2pm: Calderstones Park, Liverpool. Wed 27 April, 10am and 2pm: Royal Botanic Garden, Edinburgh. Wed 27 April, 2pm: Younger Botanic Garden, Benmore, by Dunoon, Argyll. Sat 30 April, 11.30am-4pm: talk, lunch and walk at Hergest Croft Gardens, Kington, Herefordshire.

(Photographs omitted)