Once seen, never forgotten. It’s perhaps 20 years since I stood and marvelled at the great sweeps of Anemone blanda that brighten the turf in a number of Cotswolds gardens, including that of Westonbirt School. One (not open to visitors), in a hidden cleft of the Frome valley between Cirencester and Stroud, was once home to a religious order based in Caen and, later, to Poet Laureate John Masefield and Arts-and-Crafts master Ernest Barnsley.

As spring draws on, its grassy inclines will become a haze of blue, where countless thousands of the little anemones have natur-alised so heroically. Infiltrators include a scattering of white mutations made mellow by yellow primroses and celandines, creating a Pointillist picture of exceptional beauty and simplicity.

Westonbirt School, originally the house built in the 1870s for tree- and orchid-fancier Robert Holford, stands across the main A433 road from the world-famous arboretum of the same name, but its ‘apron’ of naturalised anemones (studded here and there with wild daffodils) rivals any for cerulean magnificence.

These diminutive anemones are bone hardy and I’m looking forward to the moment when they will reappear in abundance. They’re native to a stretch of wild country eastwards from Greece to Turkestan and may be found occasionally in the company of species crocus, fritillaries, tulips and scillas. Although far from home, they have adapted to a certain kind of English terrain where chalky or neutral conditions prevail. At pH6.5, our own soil is marginally acid, but a good colony of these anemones is building up slowly in our orchard, where they rub shoulders with (and are hidden by as they die off) thuggish daffodils and fibrous-rooted Iris sibirica.

They are the first ‘bulbs’ to appear after snowdrops and winter aconites, and their delicate, daisy-like flowers are much anticipated. Several catalogues list named varieties that, understandably, cost more, but, to my mind, the original species is perfect, coming as it does in several shades of blue with the odd albino among them. It’s taken a dozen years, but they have pleasingly multiplied (a few seeding around in unexpected corners) and-who knows?-I may one day have to mow paths through them as they do at some gardens.

Our orchard at Bryan’s Ground has been transformed in recent months. Where once the 150ft arrow-straight drive ran from front gate to kitchen gable, we have built a canal. It preserves the drive’s serpentine edges, and, at night, beautifully reflects any lights that may be on in the house. Work on its completion was much delayed by January and February’s cold and snowy weather, but in the past couple of weeks, Simon Dorrell (whose design it is) has turfed right up to its brick edges, so that it already looks surprisingly established.

When it was too frosty to work with concrete and brick outdoors, our builder was happy in the greenhouse, which is also under-going change. We have removed the central staging and built in its place a rectangular pool measuring some 8ft by 4ft. It stands only 3ft high, but, by digging down another 2ft, we have a depth of water approaching 5ft. The hunt is now on for tiles for its exterior sides, where we want to mimic those decorated raised pools commonly found in the gardens of Andalusia.

The old grape vines remain in situ, and should provide enough shade in high summer to keep the water cool enough for the half-dozen koi a friend is bringing any day now. And, in readiness for the garden’s first opening after a two-year closure (and inspired by Will Giles’s Exotic Garden in Norwich), I’m raising tubs of cannas, begonias, species gladioli, agapanthus and a multitude of succulents.

Outside, four new raised veg beds have been deeply mulched. By breaking into our oldest heap-about 20ft by 10ft and made some 10 years ago-we have mined barrowloads of the most sweet-smelling compost and are distributing it around the garden with unusual largesse. And it’s comforting to see that there’s plenty left over to mulch the arboretum’s autumn-planted trees and shrubs.

Westonbirt School, Tetbury, Gloucestershire, holds its open day for snowdrops and early flowers on Sunday, March 21, 2pm-5.30pm. Garden entry, £4; snowdrop talk by John Sales at 3pm, £10

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