He was the Royal Scots Guard whose love of spring flowers has left a legacy that Scotland, and the rest of the world, still enjoys today.

Major Ian Brodie, 24th laird of Brodie and clan chieftain, began tinkering with daffodils in 1899 at his ancestral home in Morayshire, at first cross-breeding from around 49 different bulbs.

Almost immediately his experimentation had to be put on hold after joining the Lovat Scouts in 1900 to fight in the second Boer War.

In 1902, after returning home wounded, and decorated with a Distinguished Service Order, he took up where he left off and that year made 375 crosses, bearing 501 seedlings.

He become one of the world’s most successful daffodil breeders raising tens of thousands of daffodils in his walled garden at at time when the now ubiquitous spring blooms were not as popular.

Now more than 120 years later, the fruits of Major Brodie’s work can be enjoyed every year at the Brodie Daffodil Festival, held between March 22 and April 13.

Today’s daffodils are cultivated under the careful watch of Brodie Castle’s head gardener Ed Walling. At just 24, Walling oversees all of the groundwork and maintenance at the 16th-century castle which was taken over by the National Trust for Scotland (NTS) in 1980.

During his first year working on the 278-acre estate, Walling watched and waited, quietly learning the ropes and the natural rhythms of the house and gardens.

He said: “I waited to see what came up, see what grew and see what happened.”

One of Brodie Castle’s greatest assets is its daffodil collection, one of only five in the UK. It draws people to the estate and continues to flourish with every year.

Walling said: “The national daffodil collection is not just Brodie’s collection, it’s Scotland’s collection and it’s quite rare. Out of nearly 500 Brodie daffodils we only have 116, so that tells you how rare they are.”

The team is always on the hunt for more Brodie daffodils to add to the collection. Last year, two bred by Brodie that haven’t flowered for eight years made an appearance, which was “really phenomenal”. The six daffodil beds are 45 metres long by 10 metres wide, each producing around 70,000 bulbs.

Each row is planted with 30 bulbs of the 116 cultivars bred by Ian Brodie that still remain at the castle, as well as 86 others – historic and descendants.

After digging them up, the team of two full-time staff and 12 volunteers dry the bulbs out on the original racks used by their creator, before they are replanted or sold on site, as well as being distributed around other National Trust for Scotland properties.

Walling says that spreading the bulbs is vital in preserving the collection, which is vulnerable to disease and pests. This year around 20,000 bulbs were gifted to other gardens.

When Major Brodie was breeding there were only four daffodil breeders across the UK, so when an Irish friend’s collection was struck by narcissus fly almost wiping out the Fortune bulb, he sent the four remaining to each breeder, including to Scotland where Brodie’s was the only one to survive.

Many of the variants of Brodie origin were cross-bred from that last surviving Fortune bulb.

Brodie daffodils that survived are direct descendants of the 428 he bred between 1899 and 1942. Many were lost over time, gifted to others or not documented. Walling is now attempting to track down those that were sent abroad – some as far away as America and New Zealand.

Thankfully, Brodie kept detailed records of his hybrid success and failures, and of where he sent bulbs, and to whom, in his stock book – the original is still at Brodie Castle. Walling said: “The more we can get back that would be great. The collection will never stop evolving. We’re at a really good place compared to where we were five years ago and I think in five years time it will be even better.”

Duncan Donald, former head of gardens for the National Trust for Scotland, sells antique daffodil bulbs and shares Major Brodie’s fascination for the flower.

He even penned a detailed booklet about Brodie’s career as a cultivator, published by the NTS and sold at Brodie Castle.

Donald said: “The collection is invaluable in maintaining the heritage of daffodils. Brodie was very influential and his work spanned between a third and half of the time daffodils have been developed.

“Some go right back to Tudor times but on the whole they were just variants of wild plants. The main breeding of daffodils started in the mid-1800s as they began to understand about natural species and hybridisation, and the chance to bring things together that had never met in nature.”

Ian Brodie was at the crest of that wave, according to Donald.

“Brodie, in his work breeding plants, was working at a very significant time so a lot of even the modern plants that have been bred owe something to Brodie plants in their parentage,” he said.

A recognisable Brodie legacy is the darker ring around the mouth of his daffodils. He favoured touches of oranges and reds over the uniform yellow trumpets.

He also chose to name his varieties after places he visited during his wartime service including Gallipoli, Istria and Red Sea.

Despite his prolific output, Major Brodie was sparing in the number of hybrids he was prepared to put his name to, registering only 185 of his own cultivars in the RHS Daffodil Register. Donald said: “It had to be a very good plant to get through his rigorous work and he did sell off what he presumably thought was rather inferior to nurserymen.”

After his death in 1943, Brodie’s widow Violet continued to maintain and distribute his seedlings, and further seedlings were raised by Brodie Gardens Nursery. Fourteen later cultivars were registered up to 1959.

Brodie’s interest in daffodils bloomed as a young man and on inheriting his home in 1899, his interest became “a passion that became an obsession”.

“That was definitely where he made his mark. He kept meticulous records so we can see just how much work he put into this and and he did something like 12 and a half thousand crosses between different daffodils in his day.”