IT promises to be one of the most spectacular displays in this year’s Gardening Scotland extravaganza. Edinburgh’s Royal Botanic Garden’s 16m by 17m exhibit, to be unveiled at the show which opens on June 1, will include 25-foot trees, two ponds and a summer house, as well as hundreds of plants from across the world.

So far it has taken – it isn’t yet finished – ten months of preparation and involved dozens of staff. It is designed to be a showstopper with a serious message – highlighting the diversity and fragility of the planet’s eco-system through the array of bizarre and exotic plants.

But staff say it serves another purpose. Along with many of the other displays at Gardening Scotland, it will also be a gardening inspiration for the 30,000 visitors expected to flock to the three-day event at Ingliston.

The show is now in its eighth year and highlights include the Floral Hall, featuring specialist nurseries and growers from across the UK, workshops and demonstrations. And this year there will be seven show gardens, including the Garden of the Future for Scottish Water and the Recycle, Reuse, Relax Garden for the horticultural charity Perennial. The Living Garden Pavilion returns, offering advice on how to live and garden in harmony with nature, from, among others, the Scottish Crop Research Institute, Butterfly Conservation, Scottish Woodlands and the British Trust for Conservation volunteers.

But in terms of sheer spectacle it will be hard to beat the Botanics’ exhibit, on show in the Floral Hall and the biggest display ever seen at the Edinburgh event.

Pete Brownless, Botanic Garden supervisor explains: “What we are trying to show is the world’s biodiversity but I think what the public can take from it as little vignettes of plants, groups of plants which will work well together in their gardens. “Although they come from around the world, many will grow easily in Edinburgh.”

The display is split into four sections, each showing a different environment. Perhaps one of the most interesting for gardeners currently planting out their bedding plots will be the section focusing on these domestic garden favourites.

Pete says: “We are going to have a fairly extensive bedding display but rather than do a formal bedding scheme we are trying to put them together in a more naturalistic way, a bit like they would appear in the wild.”

Many people might be surprised to learn that their favourite bedding plants which flower happily in moist-rich compost in standardised rows around lawns actually originate from the world’s most arid regions.

“They are often actually desert plants which don’t flower for years, then when it rains the desert turns green,” says Pete. And the more random-looking planting scheme, rather than rigid rows, follows a similar trend in recent years with herbaceous plants. “We thought we would try it with bedding plants and we will be mixing them with grasses,” says Pete. “Many of the plants we use can be bought at places like Dobbies in full flower.” And he picks out nemesia and diascia as good species to look out for.

Another section of the garden will focus on plants which flourish in tropical conditions – not ones for windy spots in a Lothian garden, but, in many cases, ideal for brightening up in the inside of a home. Again Pete says the key for amateur gardeners looking for tips is to check the planting arrangements, particular with species which are quite new to our garden centres.

“I know a lot of people are attempting to grow banana plants these days – you see them on sale in garden centres and even supermarkets. They need a high humidity and a lot of liquid feed to help them grow but you can use them as a spectacular backdrop to a lot of house plants. It is best to put more colourful plants in front of them, like saintpaulia and streptocarpus.”

Visitors should also look out for the Botanics’ use of orchids, their delicate, colourful blooms offset by imaginative foliage behind, making up for the exotic blooms’ often drab leaves.

A third section includes rare and unusual rhododendrons, while the fourth takes in an often overlooked range of plants, but ones which can be a great boon to a city gardener with little space – alpines. The section’s aim is to recreate a European or Asian woodland, with lots of primulas, ferns, and species like rodgersia, which John Mitchell, supervisor of the alpines section at the Botanics, says is a perennial which will easily grow in Edinburgh gardens.

“Alpines, which are plants which grow in extreme conditions such as the Alps, are particularly good for city gardeners because you can grow them anywhere providing you have the right soil conditions. You do need a lot of drainage and a few stones so that the roots can run down the side but you don’t need a large garden because most of the plants are quite small,” he says.

Good examples to look out for include incarvillea – “a fairly common plant with flat leaves with a flower spike with large purple flowers” – and saxifrage, a rosetted perennial with a long white flower spike.

• Gardening Scotland takes place from Friday, June 1 until Sunday, June 3 at the Royal Highland Centre, Ingliston. Tickets in advance cost £12/£10, or on the door £14/£12. For details or to book, call 0870 850 5680.

WHAT TO DO THIS WEEK

Cover gooseberries, currants, strawberries and soft fruits with netting to keep the birds away.

Thin out plums to leave them spaced around 5-7.5cm (2-3in) apart.

Prune late spring and early summering flowering shrubs like philadelphus, weigela, ceanothus and escallonia immediately after flowering.

Sprinkle general fertiliser granules around flowering plants and shrubs and hoe them into the soil surface, watering in if the weather is dry.

Raise new plants of cytisus, deciduous azaleas and magnolias by layering low growing shoots of young growth to soil level.

Plant marrows, courgettes, pumpkins and squashes outside now.

Top up pond water levels as they fall in hot weather.

Cut your lawn at least once a week and twice for a better finish on fine lawns.

Check plants for aphids. Heavy infestation may need treating with a soap-based spray if you can’t pick them off.

Tie in the shoots of fan-trained figs growing against warm walls. Pinch out the tips of sideshoots when they have produced five leaves.

CABBAGE PROTECTION

Keeping your green guard up

THERE are many scarers on the market to keep birds off newly-planted cabbages, or you could make your own out of some string and shiny old CDs threaded through at strategic points. But sooner or later the birds will realise these deterrents are not an actual threat.

The best way to go is to grow the plants under netting. Put four stakes (such as canes) in the ground around the edge of your patch, and place fine-weave mesh sheeting or netting over them, attaching it to the posts with strong twine or wire.

Make sure your canes are cut above the plants and will hold the netting high enough to prevent birds just pecking through it.

It may also be worth placing a collar (these are available to buy from garden centres or you could just make your own from old carpet squares) round the lower part of each young plant to stop the cabbage root fly from laying eggs at the base of the stem.

BEST OF THE BUNCH

Allium

THESE bulbs, otherwise known as ornamental onions, have increased in popularity in the past decade and quite rightly so, as they are easy to grow and provide large lollipop flowers in shades of purple, pink and white in early to mid summer.

They come in all different sizes, although most are between 30-90cm (1-3ft) tall. I love the medium-sized allium christophii, but if you want a real statement look to the giants – allium globemaster, which bears flowerheads 20cm (8in) across and allium giganteum, which reaches 5ft or more and stands out in the crowd.

They will hold attention long after they have faded, the structural seed heads standing tall, adding to the planting scheme. If you’re planting them in a border, surround them with ornamental grasses which will hide the strappy leaves, that start to die away before the flowers bloom and can look a little tatty.

source : living.scotsman.com