Gardening: Subtle and sublime design

Imagine: in 1908 you inherit a large, opiate-inspired nightmare of a house with a garden requiring 30 gardeners and 36,000 bedding plants. Fortunately your sister marries a chap who seems to have some useful ideas. This struggling architect would probably love to get his hands on your house and make his name by rebuilding it, but instead you let him loose on the garden which he redesigns for free for the rest of his life. His name is Edwin Lutyens. The house is Knebworth in Hertfordshire.

At a stroke Lutyens introduced calm to the garden by sweeping away the acres of parterre behind the house and replacing the beds with a sunken lawn planted with a square of pleached limes surrounding a pond. The simplicity leaves one breathless, but the effect is perfectly still and cool. The original 1911 limes survive, beautifully shaped by brutal annual pruning and, although the lawn could be introduced to a roller, the thick turf is luxurious underfoot.

Roses have had a bad year thanks to the wet spring rust and rampant greenfly, yet the rose-garden still delights - a symphony of pink and white spreading out into ebullient herbaceous borders of blue and purple. The colours work well in the 1911 scheme - riotous from a distance yet curiously peaceful from within.

This garden is well endowed with comfortable Sissinghurst-style seats, enabling armchair gardeners like myself to appreciate it on several levels, including the meticulously simple ponds (Lutyens) and wonderfully decaying Gothic stone buckets (not Lutyens, but deliciously planted up).

Yews are a terrific structural element to play with and our as yet unknown architect planted lots of them. Not prissy little birds or twiddly balls on sticks - our man was able to see his grow big enough to sculpt into immense hedges of huge primeval forms. "Oh yeah?" they seem to say to the eye-popping house opposite. They are not diminished by niches cut into one side to accommodate some droopy Victorian classical goddesses, whom somebody must have loved. High yew hedges were also key to the garden equivalent of an air-lock, a small, plain, green garden that leads by oblique openings into my favourite place at Knebworth. Not ones for loopy names here, they call it the Yellow Garden, and it is.

Protected by those massive hedges, a tranquil pool burbles gently. The yellow and gold colour scheme is warm and restful, the balance of the design pleasing. The Japanese go to inordinate lengths of artifice and symbolism to get visitors to slow down and find peace in their gardens. Lutyens did it effortlessly.

There is a fair bit to forgive, though, as the garden generally was in need of a good haircut when I visited. Staff shortage at this time of year is a disaster in tidiness terms, but press on because this place is packed with features of such strength that they mostly overcome the pressing need for dead-heading.

The bluntly named Brick Garden actually justifies a far more frivolous moniker to catch the charm of this outbreak of typical Arts & Crafts brick paths skirting small beds and miniature lawns. I thought the actual paths were more authentically distressed than Lutyens meant, but the effect is delightful. Apart from the pergola. Oh, I am sure he made one there; I just do not believe it looked like the present incumbent. So roll on the new planting which will smother it rapidly in a conflagration of clematis, jasmine, wisteria and buddleia, reducing the sheep in the park beyond to mere sound effects.

What would he have made of the maze, always a commercial feature nowadays (unless you are rich enough not to need the public in your garden) and hideously time-consuming to maintain? The surrounding planting of ground- cover roses and decent-sized standard honeysuckles is pretty, which rather softens the point of a maze as a dark, scary place where children get lost and adults get frisky. It is more understandable than Malus walk, which is really a short totter from nowhere in particular into nowhere else. Apparently its layout is a work in progress - part of the continuing renovation and reinvention of the place.

It was probably Lutyens who asked his friend Gertrude Jekyll to scribble a design for the herb garden. It was not made, though, until 1985 when the plan surfaced in America and, Lo! another, much trumpeted, feature was born. Personally, if I had a bit of real Saint Gertrude, I would make a point of keeping it a bit tidier, especially as it relies on a severely mathematical design (a quincunx - five circular stone beds set in a diamond shape) and loses impact when the herbs have shot gloriously all over it.

There's the rub. This is a large and increasingly labour-intensive garden being bravely revived out of a private purse. To keep it petal perfect is an enormous task and, frankly, it does not matter. I enjoyed the whole place, including the clean loos, pleasant staff and the fact that the view of Stevenage is on the other side of the house. Oh, and did someone mention a pop concert?

Knebworth House, Knebworth, near Stevenage, Hertfordshire, is just off junction 7 of the A1. During September the garden is open at weekends. A combined ticket for the house and grounds is pounds 5; pounds 4 for garden and park only. Separate admission to the adventure playground in the park. For further information and special events call 01438 812 661.