Cheltenham hasn’t taken part in the National Gardens Scheme for many years and now like a fleet of London buses, not one but nine gardens have come along.

Ranging from a tiny courtyard to a medium-sized family plot, they will be opening their gates to the public this week.

When I first started writing about the area, there were gardens in the town that opened for the NGS but when those stopped the county organisation struggled to find replacements.

There have been the occasional events for smaller causes, such as town charities or groups, but nothing for the ‘Yellow Book’.

It’s something that’s always puzzled me given the charity’s strength in the rest of the county, Cheltenham’s reputation for its flowers, and the number of keen gardeners it has; the thriving horticultural society celebrates its 75th anniversary next year.

Now, as the 2016 season comes to a close, Cheltenham is back on the NGS garden-visiting map.

I’ve been along to one of those taking part to see what’s on offer.

A surprising discovery

One of the delights of a group opening in the National Gardens Scheme is that you never quite know what you will get.

Unlike individual gardens, which are vetted to ensure they will provide at least 45 minutes of interest including tea and cake, the plots in a group opening are often much smaller and very varied.

What makes a town group opening even better is that from the street there is often no clue to what those hidden back gardens contain.

It’s certainly the case with Malcolm Allison’s Cheltenham house. Planted containers at the front suggest it’s the home of a gardener but there’s little to arouse much curiosity.

I expected something typical of a suburban garden: a patch of lawn, neat borders, familiar plants with possibly one or two slightly unusual things. The reality is very different.

For a start, the garden is not neat – but that’s deliberate. Malcolm gardens for wildlife and prefers what he describes as “the natural look”.

“I like it to look natural and the opposite to gardened,” he explains, “but it’s very contrived and I do spend a lot of time on it.”

As a result, plants are allowed to self-seed, piles of old wood are placed in corners for insects, seed heads are left for birds and nothing is made too tidy.

Then there’s the lawn, or lack of it. When nurseryman Malcolm and his husband, David, moved in four years ago there was a large expanse of grass but that is now flower borders and even the narrow grass path has been replaced by gravel.

“I arrived with a lawnmower and gave that away after a year,” he says. “The grass just turned into a muddy, slippery slope so I gave it up.”

But it’s the plants themselves that proved the biggest surprise. Yes, there are the sort of things I see in many gardens – hellebores and ferns in the shady areas, pink Japanese anemones on slender stems – but there were many more that were unfamiliar.

There are unusual begonias, including B. fusca from southern Mexico, which has large, almost felty leaves, and B. masoniana, with its distinctive ‘iron cross’ marking. Daphne calcicola ‘Gang Ho Ba’, an evergreen alpine with bright yellow blooms that Malcolm is carefully nurturing and his prized possession Dendroseris pruinata, a Chilean shrubby daisy that is under threat in the wild. He’s grown it from seed and is still waiting for it to flower.

Malcolm grows lots in pots, partly to soften the patio and hard standing alongside a shed that he inherited – a second was taken down – and partly because he finds things survive better in containers in the shade than in his clay soil. A 20ft leylandii hedge that was behind the sheds has now been felled but the area is still shaded, not least because of mature apple and plum trees.

Near the house, stone troughs are used to house alpines that would not cope with either the soil or the crowded borders.

A collection of containers at the end of the garden illustrates his love of the unusual and of colour.

“In a shady situation, colour lifts it a little bit and stops it being quite so dark,” he explains, pointing to the orange flowers of Begonia sutherlandii, the coral-red of Salvia ‘Ember’s Wish’, Lysimachia congestiflora ‘Persian Chocolate’, with its yellow flowers and purple, trailing foliage, and the striking Oxalis spiralis subsp. vulcanicola ‘Sunset Velvet’, which has golden blooms above red, orange and yellow leaves.

Many of the plants are not hardy and overwinter in his greenhouses alongside a collection of nerines. Others, such as Persicaria microcephala ‘Purple Fantasy’ and Heuchera ‘Lime Rickey’ stay outside.

There are wildlife friendly and ‘green’ features woven through the garden. I nearly missed the small plant-filled pond – the garden is teeming with tiny frogs – there are several water butts, a wormery, and beehives.

Teasels thread through the borders alongside roses, persicaria, bidens, crocosmia and mallow.

“I love flowers,” says Malcolm. “Foliage is great but I like colour.”

Orange Dahlia coccinea, and numerous salvias in pots near the house fulfil this role, including inky purple ‘Nachtvlinder’, pale pink ‘Peter Vigeon’, red ‘Royal Bumble’ and blue ‘African Skies’.

The dainty flowers are often lost in large borders but in this small garden – it’s 67ft by 27ft – they more than hold their own.

“My vista is only 15ft and in a little garden, a lot of salvia flowers are perfect.”

• Malcolm sells plants at Farmers’ Markets across Gloucestershire. See his website for details.

• 79 Byron Road, St Mark’s Cheltenham, GL51 7EU, is open on Sunday September 18, 2016 from 11-5pm for the National Gardens Scheme. Combined admission is £4, children’s entry is free and there will be teas and plants for sale. Tickets and maps can be bought at any of the gardens. The others are:

• 34 Cudnall Street, Charlton Kings, Cheltenham, GL53 8HG

• Hosanna House, 43 Cudnall Street, Charlton Kings, Cheltenham, GL53 8HL

• Milton Cottage, Overbury Street, Charlton Kings, Cheltenham, GL53 8HJ

• 19 Wellington Lane, Cheltenham, GL50 4JF

• Edible Garden, Francis Close Hall, Swindon Road, Cheltenham GL50 4AZ

• 51 Milton Road, St Mark’s Cheltenham, GL51 7EU

• 22 Harrington Drive, Hatherley, Cheltenham, GL51 6ER

• 169 Hatherley Road, Cheltenham, GL51 6EP.

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