Being accepted for the National Trust’s careership trainee scheme seems like a mighty leap for a would-be gardener or countryside warden.

More than 800 people apply for the programme every year but only 21 are offered a place: eight trainee wardens and 13 aspiring gardeners. They are all trained while they work at a National Trust property and at Reaseheath College in Cheshire.

One thing almost all of them have in common is that they had no inkling of such career opportunities while they were at school. Now, in conjunction with the National Trust, the college wants to put that right by helping to raise the professional status of this work.

After discovering their vocation late in life, many trainees are giving up well-paid jobs to get on the scheme. Phil White, who trained as a warden, said: “I was an architectural technician and I just wasn’t enjoying the work.”

Like most people on the course, his change of direction involves a radical switch in lifestyle, so training has to be flexible enough to allow for affordable part-time study.

“I looked into going into this type of work with a full-time course but I just couldn’t have stood that,” said Mr White. “With this course, I get a balance of on-the-job training, work experience and college theory.”

Training is spread over three years, and trainees do five two-week sessions a year at Reaseheath, with distance-learning support and on-site visits from college tutors throughout the programme. Participants work for an NVQ level 3 in amenity horticulture or environmental conservation and National Trust staff act as their assessors.

In the four years since their inception, the career traineeships have been recognised as a crucial source of talent by some of the big gardening initiatives. For example, the course is supported by the National Gardens Scheme, which has been opening fine gardens to the public to raise money for charity for more than 75 years.

Gardens in the scheme include Richmond Park, one of the Royal Parks, said Ian Benison, horticulture manager at Reaseheath.

“The trainees take real ownership of their work at their property,” he said. “They have such pride in their property and their knowledge of the history of their property is phenomenal.”

Tasks covered go well beyond day-to-day gardening. Trainees work on designs for their home property and wardens assess how best to manage a heathland landscape, accounting for the demands of conservation and visitors’ needs.

“We do some practical work here,” said Neville Leader, who oversees the training of wardens. “We fill in the gaps. For instance, we might have people coming from a property where there are no dry-stone walls, so we’ll give them a chance to work on dry-stone walling.”

At the end of each week at Reaseheath, gardeners and wardens are tested on plant species identification and knowledge of English and Latin names for plants and animals. They learn 20 species per week and most trainees usually score 100 per cent.

Many of the other trainees already have jobs waiting for them at the end of the course. Some will continue with the National Trust, while others will work for various conservation organisations with the Trust’s blessing.

Allison Levee, who was on the warden course, worked at Hadrian’s Wall. She joined in the hope of qualifying as a warden for a local authority. She has had many jobs, including selling train tickets and being a photographer but now feels she has made the right choice.

“Jobs like this were never mentioned by our careers teacher,” she said. “I said I wanted to work outdoors, I wish I’d been told then - it would have saved a lot of time.”

Lucy Dean decided to be a gardener after seeing National Trust gardens at Lanhydrock House, in Cornwall, during family holidays in the county. She now tends the gardens there. Her two elder sisters have been to university but Lucy’s decision to follow the careership programme when she was 18 did not concern her parents.

“They were great,” she said. “They said, ‘So long as you’re furthering your career and you’re getting the experience and qualificationsI’ It was comforting to know that the National Trust thought that having a degree in horticulture didn’t necessarily qualify you as a gardener.”

For more information, see www.ntjobs.gov.uk and apply in the spring