They orchestrate the most harmonious displays in towns and cities, but a competitive note is struck at the National Garden Show, finds Robert MacLeod

THE plants may seem delicate but the competition is tough - particularly among the parks department staff of the councils who are aiming to pluck up the unofficial Flower of Scotland title for their own areas.

Several councils are bidding for the title. At last year's show, the Thistle Trophy and a Royal Horticultural Society Gold Medal were won by South Lanarkshire. The same council also took the Wigan Trophy, the RHS's accolade for the best local authority exhibit at any Royal Horticultural Society show during the year.

''Their success proved that standards achieved at Strathclyde last year were second to none,'' said show director Stephen Bennett.

''The South Lanarkshire exhibit created the benchmark which all the councils competing this year will be out to exceed.''

The resulting challenges have a lot of pride and prestige at stake and this year, in addition to RHS medals, the local authority entrants are competing for a new Thistle Trophy. Shaped in purple and green crystal, it was commissioned for the Show from Caithness Glass.

For their 1998 bid, South Lanarkshire has chosen a Fire and Ice theme. Red, yellow and orange blooms are used to simulate the energy of a volcano while the iceberg contrast is achieved by using a blend of plants with grey, blue and white flowers and foliage.

Rival neighbours North Lanarkshire mount their strong bid for the l998 title. Their Gardener's Palette features a giant paint brush entrance and a clever picture-frame exit. The theme continues with a Painted Lady butterfly, a colour pool, palettes of flower, and a sparkling paint tube fountain.

Equal rivalry exists between the city parks department experts of Glasgow and Edinburgh.

Glasgow returns to its acclaimed Slate Thistle theme of last year. This time incorporating two water features and a blaze of colour - a mixture of foliage plants, begonias, and other flowers. The city will also show examples of the floral designs which are created for special displays at council functions and receptions.

Edinburgh enters this floral ''old firm clash'' with a major display of plants and flowers to be seen in and around the capital's parks and urban forests. Once again, their exhibit is presented by horticultural trainees working on Capital Skills, the council's vocational training project. A similar team of Capital Skills trainees created the l997 Edinburgh exhibit which won an RHS Silver Gilt award.

For the local authority gardeners of East Lothian, the show is an opportunity to emphasise that they are now in year three of their ''Scotland's Gardens'' five-year environmental improvement programme. They are celebrating their progress with a scaled version of a

typical East Lothian local park, some of that local authority's famed floral sculptures, and a miniature bandstand complete with musical instruments.

But the Scottish local authority entries don't have things all their own way.

The challenge from outside Scotland includes the award-winning City of Belfast Parks Department. The popular team are well-known participants in the annual Ayr Show and were award-winners at last year's Royal Highland Show at Ingliston.

For their appearance at Strathclyde Park, they head up their exhibit with a display of tropical plants drawn from Belfast Council's Palm House.

Despite the fierce competition, many of the parks people have given vital behind-the-scenes help to ensure the show goes well. And their efforts are much appreciated.

''Their skills and adaptability are legendary,'' said Susan Oliver, the show manager. ''The quality of their work is outstanding.''