The past three winters have severely tested plants in Scotland.

Only the toughest specimens could survive the icy winters of 2009 and 2010, and growth this year has been painfully slow. Fortunately, the country's annual horticultural bonanza, Gardening Scotland, takes place at the Royal Highland Centre next weekend and will be full of growers who can recommend species to withstand extremely low temperatures.

A run of mild winters before 2009 had lulled Brian Young, of Holmes Farm Plants in Ayrshire, into a false sense of security. "There is quite a list of plants I have loved and lost, mostly because I was pushing the borders of hardiness," he tells me. "The biggest collection of plants I lost were the agapanthus. There were around 96 mature cultivars in large tree pots in the polytunnels. All perished despite my best attempts."

Young now demands his plants be "tough and garden worthy". Helen Knowles, of Tinnisburn Plants near Canonbie – 200m above sea level – shares his outlook. "I grow the plants as naturally as possible, which means no grow lamps," she says. "In terms of criteria for hardiness, I try a lot of plants in the garden and if they do well I can be confident they will thrive in most locations. Over the years I have tried to grow many different crocosmia, including Star Of The East. Sadly, having lost all apart from Lucifer, it is the only crocosmia I sell."

Gavin MacNaughton, of Macplants in East Lothian, has an excellent selection of species to meet the needs of Scottish gardeners. He reckons hardy geraniums are ideal. "Early-flowering cultivars including Geranium sylvaticum Album and G phaeum forms are tough and easy plants which withstand poor weather. Cultivars and hybrids, including Kashmir Blue, also make a good choice."

In addition, Macplants carries a variety of plant families and is held in high regard for its collection of meconopsis. "There are all sorts with a long flowering time," says MacNaughton. "At Gardening Scotland we will be exhibiting the clonal-raised big blue poppies. They require a fertile, humus-rich soil in an open situation but out of direct wind. There is a large range of these plants with different flowering heights and times and flower shapes and colours."

Knowles also hopes the clear, pale-blue flowers of Meconopsis Lingholm will be ready in time for the show. She's casting her net further afield too. "I've got a batch of Symphyandra cretica, a low-growing, upright perennial," she says. "The plants are covered with pale, silvery-blue bells – very similar to a campanula flower. I've never grown it before so it's exciting to finally see them in flower. I'm also hoping the perennial cornflower Centaurea montana Violetta will be in bloom. I had some at Gardening Scotland last year and they were a real hit."

Drawing on their experience, Scotland's best growers will be delighted to advise on plants for your garden. If you can't make it next weekend, head along to Brian Young's garden at Drybridge, by Irvine, which he is opening for Scotland's Garden Scheme on June 9 and 10 from noon until 5pm. n

Gardening Scotland is at the Royal Highland Centre, Ingliston, from Friday until next Sunday. Visit www.gardening scotland.com.

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