An interview with Alan Titchmarsh as he celebrates 50 years in horticulture - plus, find out what else needs doing in the garden this week.

By Hannah Stephenson

TV gardening guru Alan Titchmarsh is looking forward to getting his hands dirty at RHS Chelsea Flower Show this year.

Instead of wearing a sharp suit to present the show, for the first time in 30 years, he will be wearing a pair of gloves and designing a garden instead.

Obviously, there's a substantial chance it will be rather good, too - not only is Titchmarsh one of the country's best-known gardening presenters, but back in 1985, when Titchmarsh last designed a garden at the prestigious Chelsea, he was awarded an RHS Gold Medal for his Country Kitchen garden.

He will also be joining forces with another RHS Chelsea Flower Show Gold Medal winner, Kate Gould, to create From The Moors To The Sea - a celebration of 50 years of the RHS Britain in Bloom campaign, to represent how 300,000 volunteers help to make Britain bloom and explore Alan's relationship with horticulture through his life.

"It's 50 years since I started work as an apprentice, so I thought I could either do a 1960s-style garden through to the 21st century, but the sixties were a bit dull, all rose beds and lawns.

"So I thought, why don't I demonstrate where I first started, which was the Yorkshire moors, up to where I garden now, on the coast on the Isle of Wight?

"So we will be sloping from moorland at the back, with dry stone walls, coming down to a seaside garden at the front. It's 50 years of 'my journey', to use the X-Factor phrase.

"It's also showing the British Isles and its variety. Being a cool temperate set of islands, the range we can grow is incredibly wide and this will show the richness of the British Isles."

He'll be featuring pines, heathers and birches from the moorland, through wild flowers, down to seaside plants including echiums and cabbage palms. It will be a 10m by 15m microcosm of British gardens and landscapes.

It sounds great, but how does Titchmarsh feel about not presenting the Chelsea coverage for the first time in 30 years?

Last year Titchmarsh announced he was stepping down from the BBC's coverage of Chelsea after programme-makers offered him a more 'limited' role, although he remains RHS vice president and first ambassador.

"[I feel] wonderful," he insists. "I'm putting a show garden together - I've done it before and I love doing it. It's technically an exhibit but will look like a show garden. It's not being judged but the same criteria and standard of finish will have to be there."

"I've moved on," he continues. "There was disappointment but it's gone, I'm over it. There's no point in dwelling on things."

It's all part of a new beginning for Titchmarsh, who began his career as that apprentice for Ilkley Council, before becoming the face of BBC2's Gardeners' World for six years until 2002. He also presented Ground Force, How To Be A Gardener and several natural history series, and has written a number of bestselling novels and has a regular slot on Classic FM.

He's had eight years presenting an afternoon chat show too, though this is also ending after its last run in autumn.

"It's better to stop doing something when you're still regarded as being successful, while people are still watching, rather than it going off the boil. It will be my 15th series in the autumn, that's eight years.

"It's every day. Jonathan Ross and Graham Norton do one a week. I do five. I thought, let's stop while it's doing well."

He's certainly got enough else to keep him occupied too, with forthcoming TV projects including a two-parter about the gardens of Buckingham Palace, out in December, a new series of Love Your Garden in the summer and a series called Britain's Best Gardens for ITV, in which he explores 30 of Britain's best domestic gardens. He's also just launched a new gardening range with Waitrose, though he won't reveal if his Chelsea garden will feature any of the new products.

Incredibly, he sees all this as 'slowing down', saying that with three grandchildren to enjoy and his landmark 65th birthday coming up in May, he hopes to cut down his workload.

"I'll never stop but I want to pace myself a bit more."

Well, perhaps a little.

Best of the bunch - Magnolia

These amazing trees and shrubs can form the focal point of a garden in spring with their enormous goblet-shaped blooms in shades of pink or white. I love the stand-alone impressive M. grandiflora, which is really a tree, which will reach 7m (21ft), bearing creamy white blooms, sometimes as large as dinner plates, between July and September. Alternatively, go for large shrubs such as M. x soulangeana, whose flowers are borne on bare stems and vary from white to pink to violet-purple, or the more compact star magnolia, M. stellata, which grows to around 3m (10ft) bearing brilliant white, slightly fragrant, star shaped flowers in early spring. Magnolias will grow in any reasonable garden soil enriched with humus, in full sun or light shade.

Good enough to eat - Catch crops

The vegetable patch doesn't have to be bare while you wait for the warmer weather for planting crops like French beans, tomatoes and courgettes - catch crops will fill in the gaps. The idea is that you will be able to harvest them before planting tender crops. Good catch crops include radish, spring onion, spinach, oriental greens and lettuce. Sow them in short rows and they should be ready before the later crops are planted out in May. If you have room, leave space for the later crops and you can continue to harvest the catch crops while they are settling in.

What to do this week

:: Prune spring-flowering shrubs over three years old as they finish flowering

:: Sow sweet peas directly into their flowering position

:: Sprout maincrop potatoes and plant sprouted tubers of early varieties

:: Sow and plant out vegetables including beetroot, broad beans, carrots, celeriac, onions, peas, spinach and swedes

:: Sow seeds of tomatoes in a heated propagator or on a warm windowsill to grow outdoors when all danger of frost has passed

:: Tidy up ivy growing on walls, using shears

:: Clear remaining crops such as leek and celery, so the ground can be prepared for new ones

:: Keep the kids amused by sowing some giant sunflowers with them, under glass or outdoors when conditions allow

:: Give roses a top dressing of fertiliser

:: Thin early sowings of lettuce