Hydrangeas: a National Collection of enlivens the gardens of Lagg House in Scotland

From the garden of Lagg House in South Ayrshire, there are spectacular views across the Firth of Clyde to the rugged peaks of Arran. Here, above the Heads of Ayr – great granite cliffs that dominate the coastline – there is little to stem the ferocious winds that sometimes come blowing up the channel, which opens to the Irish Sea on one side and to the Atlantic on the other.

Fortunately, the plants that Anne Greenall has chosen for her garden could not be better suited to these particular conditions. Anne holds a National Collection of hydrangeas and, from mid summer until the end of autumn, they produce exuberant inflorescences that billow outwards from the borders in great waves of dramatic colour.

This is a plantswoman’s garden and, even though her knowledge of the species is encyclopaedic, Anne resists any attempt to describe herself as an expert. ‘I don’t consider myself a gardener; it’s just that hydrangeas happen to suit my garden.’ She arrived here more than 50 years ago. In those days, the lawn was where her children cantered their ponies and played with the family dogs, but then someone gave Anne a hydrangea in a pot and, when it had finished flowering, she thought that it might be best to plant it outside.

That original hydrangea flourished so rapidly that Anne decided to plant another and so began a collection that has grown to more than 200 plants, including rare species, climbers and cultivated varieties. The show starts in late June, when the first of the buds starts to open, and by mid August the garden is awash with great flowerheads in every shade from pale pink to dark purple. In the damp, mild climate of south-west Scotland, the plants grow rapidly and the heads, which are not in fact flowers, but bracts that hold tiny flowers at their centres, expand to enormous dimensions. Amid this profusion, the spikes of Hydrangea paniculata explode skywards like white-hot rockets.

Anne can name most of her collection at a glance – even when they are not in flower – although she says many plants are sold incorrectly labelled and confusion can arise, so she always welcomes the opportunity to compare notes with other growers. Among her own collection she has many favourites, including Hydrangea serrata ‘Preziosa’, the leaves and heads of which are saturated with carmine shades that deepen with age. ‘Hydrangea paniculata ‘Pee Wee’ is another fantastic plant – its heads are enormous and Hydrangea macrophylla ‘Blaumeise’ (Teller Series) is one of the best in the garden. I can cut it back quite severely and still get flowers.’ Aside from this particular macrophylla and the paniculatas, which respond to more vigorous pruning, most hydrangeas do best when they are left to their own devices. Cutting them back only serves to remove the buds and results in a year without flowers.

Along the driveway that leads to the road, a belt of mature sycamores provides the shade that hydrangeas need to flourish. Beneath them grow dense plantings of Hydrangea macrophylla ‘Générale Vicomtesse de Vibraye’ and also the gorgeous H. macrophylla ‘Blue Wave’. ‘Hydrangeas are woodland and maritime plants and, because we get little frost here, there is little to check their growth,’ says Anne.

Just to be on the safe side, however, she leaves the spent heads in place until spring so that they will provide some protection for the emerging shoots. Then when she removes them she presses them down among the roots: ‘That’s all the feeding that most of them need, otherwise you will end up with lots of leaves and not so many flowers.’

Moisture, on the other hand, is essential and in the west of Scotland it is seldom in short supply. Ground that is permanently sodden will cause the roots to rot, but despite rainfall levels that is not a problem at Lagg House. ‘The stone beneath us is granite,’ Anne explains. ‘So although it holds water, it also drains and it is, of course, highly acidic, which is what hydrangeas love.’

From early spring, Anne starts checking for signs that flowerheads are beginning to form and she follows their progress with anticipation until they start to open. Then she cuts armfuls of blooms and brings them indoors, placing them in vases around the house. Even dried, they continue to delight her long after the hydrangeas in the garden have gone over.