Prison horticulture keeps a low profile. But behind the high walls and fences, many establishments have been quietly upgrading their horticultural facilities in recent years. Meanwhile, on the outside, enlightened employers are providing ex-offenders with an opportunity for rehabilitation and development.
A controversial programme to replace traditional prison farms with horticultural facilities took place between 2003 and 2006, bringing with it investment of nearly £1m in prisons' horticultural equipment.
According to one prisons service adviser, who asked not to be named: "It became evident there were fewer job opportunities outside in agriculture, though there were still plenty in horticulture - we hear of thousands of low-skilled places going unfilled. Also, most prisoners are town-based, so they are more likely to find work with a parks department than a farm on their release."
Prisoners also find the work itself more appealing, he adds. "In the past there were only a few motivated enough to get up at 4am to milk the cows." By one estimate, fewer than 300 inmates were involved in farm work nationally when the programme was wound up.
So with the blessing of ministers, the agricultural land belonging to 23 prison farms was sold and the revenue invested in glasshouses, horticultural machinery and staff training. "Now we grow predominantly under glass or in polytunnels and our staff are fully qualified to deliver the NPTC (National Proficiency Tests Council) training to prisoners," says the adviser.
The move also fitted in with the green agenda, he adds. "When we were growing field-scale, the vegetables were often sent away to our own preparation plants. Now a prison's crop tends to be used at that prison." Indeed, today's prisons even have biodiversity action plans, he adds.
Some prisons had established strong reputations in horticulture even before the change. HMP Leyhill in Gloucestershire is a regular exhibitor at the RHS Chelsea Flower Show - its success there even spawning a film, Greenfingers, starring Clive Owen.
Yet training in prison remains somewhat ad-hoc. According to an Ofsted report published last month: "There is no single national system for recording offenders' progress and achievements in learning and skills." Yet it adds: "The recording of progress and achievement remains critical in monitoring learner success and evaluating the effectiveness of programmes."
The report recommended the development of "pre-release support for skills for life, employment and training opportunities from commencement of sentence to release".
At present, there is a dearth of information from the Government and its agencies such as Nacro - formerly the National Association for the Care & Resettlement of Offenders - on whether such programmes do indeed lead to offenders increasing their chances of employment on release.
The prisons service adviser explains that boosting employment prospects is just one among several incentives to motivate prisoners. "We can't force anyone to get involved but part of the motivation for prisoners is that it's time out of the cell," he points out.
"Generally, they're people who've never handled plants before and it frequently has a moderating influence on them. Some just enjoy working outside for a change; however, this is dependent on the type of establishment. But for a substantial number it is an opportunity to gain skills, experience and a qualification that will put them in better stead when their sentence is over."
Moves are already underway to formalise training and ensure offenders emerge with recognised qualifications to show to possible employers in the sector, he says.
"Research through potential employers asking what qualifications they would like potential employees to have has led us to offer NPTC City & Guilds and NVQs, which include basic horticultural skills and machinery operation qualifications, leading to certificates of competence."
But even those prisoners who have not gained horticultural experience while inside still find that the sector provides opportunities on release.
Blue Sky Development & Regeneration is a not-for-profit company set up three years ago by the charity Groundwork Thames Valley to provide ex-prisoners with paid work in areas such as grounds maintenance.
Employment and training manager Frank Hough, himself an ex-offender, believes the company is the only one of its kind.
"Some have experience," he says. "But most of it is work such as mowing and strimming that can be learned quickly."
But the company also takes training needs seriously. Through the Government's Train To Gain programme, Blue Sky encourages workers to attain NVQ Level 2 qualifications in amenity horticulture.
"We will get them a CSCS (Construction Skills Certification Scheme) card for construction site work and even put them through their driving test," he adds. "But it's also about taking responsibility, developing a work ethic and gaining self-esteem."
Blue Sky works with ex-offenders who have been referred to it by the probation service, Jobcentres and others - but they have to pass an interview in order to be given a six-month contract with the agency, which continues to provide training and support after the initial period.
The scheme boasts a 47 per cent success rate for getting clients onto regular employment. Over the three years of the scheme, 15 per cent have reoffended - well below the national average of over 50 per cent.
Nor is quality of work sacrificed in the name of rehabilitation. According to the company's website: "We must match or improve on the quality available elsewhere."
Hough says that behind the enlightened ideals of Blue Sky lies a firm business case. "On the back of successful placements we get more work," he says.
He is not concerned about the effects of the downturn. "Work will be more difficult to find in construction. But now a lot of foreign nationals are heading home, which suits us."
Yet there may be a limit to what such schemes can achieve. Director Guy Moreton of recruitment agency MorePeople says it is still almost unheard of for ex-offenders to reach management positions.
"I am a big believer in rehabilitation, and in giving people a second chance to prove themselves," he says. "But it would depend on what they were convicted of - there's a line to be drawn with serious crimes."
Moreton adds that those who were already working in the sector and have then spent time in prison will also find it difficult picking up their career. "But then it's difficult to recruit someone who's been wandering round Africa for three years, too," he says, "as their skills are out-of-date."
However, Camden Garden Centre in north London, which is owned by a charity whose remit covers employing people from disadvantaged backgrounds, including ex-offenders, believes in its approach.
Head of social enterprise development and training Mike Jackson says: "A lot of them have never had a job or a qualification. They may not be that bothered when they first come here, but usually after two months it's got a hold of them."
Recruits stay with the garden centre for up to two years before moving on, often within the industry. But Jackson adds: "With a criminal record, many find it easier to go self-employed, in areas like gardening."
Jackson also sits on a panel with Natural England and the Forestry Commission, looking at ways of reintegrating offenders through work in green spaces. "Anecdotally, that kind of work is very beneficial for offenders, and sympathetic employers recognise the value of that," he says.
So low is the profile of the Windlesham Trophy that not even the press office of the co-organiser, the RHS, knows of it. Yet the award, which honours the best in prison horticulture, marks its 25th anniversary this year.
According to a prisons service adviser: "There are potentially 120 prisons involved, but we end up with about 30 entrants each year."
These are then whittled down to four finalists, which are then visited in person by a panel of RHS-appointed judges.
Among the judges is Chiswick House head gardener Fiona Crumley, who has been a competition judge for the past three years.
"The entrants are very impressive, both for the horticulture and how they achieve it," she says. "(2008 winner) HMP Wymott produces fantastic bedding plants in its nursery. Another entrant, HMP Sudbury, does some of the most impressive hanging baskets I've seen. They also have a strong commitment to wildlife and to waste recycling."