3 Feb 2025

The PLANTS project: three west coast gardens

Written by Fran Culverhouse, PLANTS West Inventory Officer

Standing in the woodland garden of Brodick Castle and looking out to sea, just visible between the very tall trees!

Brodick Castle Garden

As part of the PLANTS project, Fran Culverhouse and the South & West team have been auditing a selection of our west coast gardens: Arduaine, Brodick and Crarae. At these places, a unique microclimate — nurtured by the Gulf Stream — creates ideal conditions for rare and extraordinary plant species to thrive.

Imagine strolling through gardens where exotic plants from far-off continents flourish, showcasing vibrant blooms and unique foliage rarely seen in the UK. From towering tree ferns of the South Pacific to aromatic evergreens of Tasmania, we uncovered treasures that will inspire gardeners and plant lovers alike.

Our focus was on three remarkable gardens: Arduaine and Crarae in Argyll, and Brodick Castle on the Isle of Arran. These gardens exemplify the effects of the Gulf Stream, which provide wetter, more humid conditions and milder winters compared to other locations at the same latitude. Inverewe, another iconic west coast garden, also owes much to the Gulf Stream, but it was outside the scope of this team’s review and is not covered here.

We found ideal growing conditions for plants whose native habitats have a similar climate, including many from the southern hemisphere. As a result, species thrive here that are not commonly cultivated in the UK or may require protection in other parts of the country. Examples include tender tree ferns, exotic rhododendrons and a diverse selection of flowering shrubs that would struggle in cooler, drier climates. One effect of this microclimate is a faster rate of growth; another is species producing viable seed or spores that rarely set seed in cooler parts of the country – interesting hybrids can occur as plants within the collection cross-pollinate.

Two very large tree ferns - ferns with chunky, tall trunks like trees - grow at the edge of a woodland area, with smaller ferns surrounding them.

Tree ferns with self-sown sporelings at Arduaine Garden

It was a real treat to explore the collections at Arduaine, Crarae and Brodick, which contain so many botanical treasures. The PLANTS project received great support from the head gardeners and their teams, and we were especially grateful for help identifying the unusual plants we hadn’t come across before. Since our time auditing in the gardens, we have added all our findings to our IrisBG database to assist with the future care and management of these special places.

For plant enthusiasts and casual visitors alike, these gardens provide a glimpse into the extraordinary possibilities of nature when climate, plantsmanship and care align. Here is just a small selection of the interesting plants we encountered, which enjoy the mild and moist microclimate in these gardens (please open each image for more information):

A close-up of a shrub with long waxy green leaves and a cluster of little white flowers.

A close-up of a small branch from a tree with dark green, almost holly-like leaves and pinkish buds growing halfway along the stem.

A close-up of a tree with a honeysuckle-type flower. The flower is deep pink with yellow tips on each strand. The leaves behind are a deep green and have a toothed edge.

A close-up of the dense branches of a cedar tree, with young pale brown cones forming at the ends of branches.

A close-up of a fuchsia flower with a yellow base and purple/pink stamen. The petals fold over and out, and are green and brown.

A close-up of a bright pink flower, shaped a little like a star, with brown leaves in the background.

A waxy green fern frond lies on a sheet of paper.

A tall, cone-shaped tree grows beside a stone garden wall, which has an open gate through it.

A close-up of a feathery frond of fern, which is mint green.

A close-up of an unusual looking flower. It is deep pink with yellow tips. It slightly resembles a mass of squirming worms.

A tall tree with thick branches grows in a woodland, surrounded by smaller shrubs at its base. Moss grows on its lower limbs.

Plant Listing at the National Trust for Scotland (PLANTS) is the biggest horticultural audit project undertaken by the Trust and aims to celebrate, protect and better understand the flora and vegetation across our gardens and designed landscapes.