And now for the shrubbery

We have a garden of two acres which we have developed over the past 12 years. The two of us are the only gardeners so we tend to undertake a project a year. We have agreed that next year's project has to be the front of the house muddle. And here I am bereft of ideas.

The front of the house faces east and gazes out, across a gravelled drive, to a sort of Victorian shrubbery - the remnants of, I suppose. The trees, as they mostly are, include a fine variegated holly tree, a slightly unconvincing English yew (it needs more space), laurel and box. There is also a weeping elm and a terminally ill hemlock.

All these are bordered on their east by a mixed hedge which screens a country road, and are undercarpeted by scraggly hypericum, some ivy, archangel and really robust marestail. My husband feels we should remove the laurel and hemlock and do some enthusiastic pruning and shaping. I am terrified of giving the marestail any more light: we haven't eradicated it anywhere else in the garden and have been forced into lateral semi-solutions. The border, though, is a formless muddle, but important, as it is the first glimpse any visitor gets of the garden. I don't want to begin wholesale destruction without a clearer idea of the outcome. Can you help, please?

Lesley Kant and Steve Cunneen live in the kind of house that is the stuff of town-dwellers' dreams: an 1820s vicarage surrounded by its own land, on the edge of a Norfolk village. They did plenty of dreaming of their own before they bought it, 13 years ago. At that stage they were living in a terraced house in London, she working as a schools inspector, he as a project manager for Barclays. The London garden whetted their appetite for more, but when they bought the house, with its two acres, Steve said they "didn't know what an acre looked like. It was just something farmers talked about."

Not much had happened in the garden since the previous owners had bought the vicarage from the church, three years before Mr Cunneen and Ms Kant came on the scene. A job lot of conifers was dotted about (most now removed - hurrah!) and the beginnings of a herbaceous border laid out. But a phenomenal amount has happened in the last 12 years. Mr Cunneen and Ms Kant are the best kind of gardeners: observant, patient and perfectionist.

Since the remnant of the shrubbery described in Ms Kant's letter was one of the few mature features they inherited, they left it alone while they planted hedges, dug vegetable gardens, planted trees and trained topiary (and much more) in the rest of the garden. Now the shrubbery's time has come.

In her letter, Ms Kant calls it "important", as the first bit of the garden that visitors see. Yes, that is true, but it is not important in the sense that it needs to draw attention to itself. As you turn from the lane into the vicarage gate, the shrubbery is on your left, with a big, gravelled parking area in front of the house, which is on the right. So you are as likely as not to see the shrubbery sideways on. It will never be important as a special "feature" in the way.

The shrubbery's role is as a backdrop, which ought to remain sympathetic in style with the house which it faces. And, most important, it must continue to shield the house from the east wind which in this flat land can be a killer.

You have to go through this general kind of preamble before you can get down to the particulars of a planting scheme. You should have a clear idea of what the plants need to do before you can start suggesting suitable candidates. And here, of course, the main players are already in place.

The planting sequence starts on the curve, as you turn into the drive, with the strange little weeping elm. It is dotty rather than beautiful (and not part of the original period planting), but curiously appropriate. After the elm, is the big yew at the back of the shrubbery. The superb variegated holly is planted right in the foreground and reaches out over the gravel. It may originally have been clipped as a topiary specimen. That would make its position more understandable. Behind it is the dying hemlock, then English laurel in the background, with a spreading box tree in front. A fine, small weeping horse chestnut fills the back corner. The shrubbery is about 15ft wide and 30 yards long.

Before putting in any new plants, they obviously needed to assess the existing plants and decide what they were going to keep. "Well, the hemlock will have to go," I said unfeelingly. Two of its three enormous uprights had already died, and only wisps of life remained in the third. It was "going back", as the kind, euphemistic phrase has it. But Ms Kant couldn't bear to cut it down while there was still a whisper of life in it. So it will stay, and act as a clothes-horse for a climbing Vitis coignetiae.

That cuts down the space for putting in new plants, but it doesn't matter. I have exactly the same feelings about a ridiculously sick lilac in my garden - one of the few remnants of the original planting there.

The laurels could be substantially reduced, without affecting their usefulness as windbreaks. I suggested that Ms Kant took out at ground level several of the large branches that were growing forward, which would release space for some contrasting shrubs. The yew had a couple of seedling elders interfering with it which needed to come out. It would look better, too, I thought, if the ivy were stripped from the bark, which glows a delicious, rich, oxblood colour in wet weather.

Towards the back of the shrubbery there was room for a couple of quiet shrubs which would not mind deep shade and which would add interest to the mix, while fitting in with the predominantly 19th-century ambience of the planting. I suggested Decaisnea fargesii, with wonderful long pinnate leaves. It can be stooled down to keep it at whatever size you want - a useful trait in this kind of situation. And - because Ms Kant likes hydrangeas and hasn't got any - H sargentiana, which has huge paddle leaves with the texture of sharkskin.

For the foreground, the handsome mahonia `Charity' and either another pale-flowered lacecap hydrangea such as `White Wave', or a flat-tiered viburnum such as V plicatum `Lanarth'. All the shrubs would need to go into big holes, well packed around with good compost and bonemeal. And mulched annually. This is a hungry, thirsty billet for them. But, properly looked after, they will cope. And these two gardeners certainly know how to look after plants.

The least successful section of the shrubbery is the first bit, on the curve by the weeping elm. Ms Kant had tried grassing it, so that by mowing, they might see off the marestail. But the marestail still flourishes, the grass doesn't grow because of the shade, and it looks inappropriate. The rest of the shrubbery is carpeted with ivy.

I suggested they did away with the grass, and tried lenten hellebores, putting them in as big plants. Not the posh kinds. Tough, cheap ones that will flower before the marestail gets its head above the ground. In between, ferns such as hartstongue, and the marble-leaved Arum italicum `Pictum'. The circle inside the cage of weeping branches from the elm could be filled solid with autumn-flowering cyclamen.

As for the rest of the underplanting, I would get rid of the hypericum and encourage the ivy, by sifting some compost over it during the winter. This will please the marestail, too, but that can't be helped. Mr Cunneen and Ms Kant will have to cut down the most dangerous spears and live with the rest. If they haven't managed to kill it over the last 12 years, they will probably not do so over the next 12. Snowdrops in the ivy. Scillas, too, in the more open sections. And more ferns, especially those (such as the polypodies) that don't mind dry situations. Since the time of the dinosaurs, they have learnt to fight for their Lebensraum against the bullying marestail.