N EARLY 25 years after snowdrops first began melting her heart, Jo Hynes' passion for these shy little celebrities shows no sign of waning.

On the contrary! As custodian of around 150 different varieties at Higher Cherubeer, near Dolton, Jo buys and swaps and talks snowdrops with all the zest of a stamp collector.

Fact is, all galanthophiles are a fervent bunch. Snowdrops — or galanthus after the Greek gala for milk and anthos for flower — have become cult plants these days, with at least one specialist nursery staging an annual tender sale of rarities and another distributing a list that includes one variety costing a breath-gulping £150 . . . for a mere single bulb.

It's all serious stuff.

Fewer flowers are purer and simpler than snowdrops. No one, however, should think of them as "just a little white flower seen in gardens and woods". There's much more to galanthus than meets the eye, albeit in a format that's often subtle in the extreme.

Hard to believe, then, that as well as the genus' 19 species, nigh on 1,000 varieties abound — and if that's hard to grasp just wait until you read national "galanthus godfather" Matt Bishop's latest snowdrop "bible" due out in the next few months.

Jo — North Devon organiser of the National Gardens Scheme that raises thousands for charity — says of the snowdrop: "They are beautiful things but they seem to have a strange aura about them.

"In fact, I do not think anyone would bother with them if they came out in the summer." A fascinating observation from an enthusiast and, probably, true as the virginal blooms would quickly become lost amid so much lush foliage. Apart from that, they would lose the ability to lift our spirits on those wet and windy days of February.

Jo herself first began looking twice at them back in the 1980s when she was living in Buckinghamshire.

She became founder-chairman of the Bucks, Northants & Oxfordshire Hardy Plant Society and, during her tenure, met up with a grand lady of the garden, Gwladys Tonge, who, by a rare coincidence, I had myself interviewed more than ten years earlier when she lived in Warwickshire and I worked in nearby Coventry.

It was Gwladys — now three months shy of 90 — who introduced Jo to the art of snowdrop growing. "She was a real inspiration," says Jo and, not surprisingly, the pair have remained friends.

When Jo, husband Tom and two young children moved to Cherubeer 19 years ago she planted five different varieties, each one forming a natural carpet of white. Over the years her collection has burgeoned to around 150 names and thousands of blooms unfolding from as far apart as October to April.

Most, though, are the classics that herald the arrival of spring — or midwinter in the case of 2010 — and break from bud with a defiance against frost's icy grip and a toughness that belies an apparent fragility.

Bizarrely, snowdrops have built up an unprecedented following despite always being white-dominant and, to the untrained eye, all looking pretty much alike.

Yet gaze intently and you'll spot those elusive changes in the green marks on the petals, you'll notice some are double flowered, some hang their bells down lower than the norm, some petals are spikier, some — like Galanthus gracilis — have twisted leaves, species elwesii grows to a lofty 8in with glaucous foliage, while its near-twin has earned the unofficial tag Greentip, leaving EA Bowles, our £150 candidate, sporting pure white inner petals the same length as the outers to create an exquisite sphere.

Not overlooking those coloured gold on petals and ovary. The two best-known are the double Wendy's Gold that was discovered in a hill fort near Cambridge and Sandersii, a single type first seen in Northumberland, along with its double form Lady Elfinstone.

So, although snowdrops are dwarfs, they are far from snow white!

All are fragrant to a greater or lesser degree, though only galanthus gurus will bother to strain their sinews for an aromatic lungful. Others will grow them in pots . . . and take a sniff at eye level.

Whether you're on all-fours or upright, you'll sense an olfactory of delights, ranging from honey and bitter almonds to mossy, as exuded by the common snowdrop, nivalis, while popular variety S Arnott boasts the strongest honey perfume of them all.

Jo had planned to host two customary NGS snowdrop days at Cherubeer, but was forced to cancel the first after snow and ice on January 31 had left all her flowers prostrate and frozen to the spot.

"It wouldn't have been much fun looking at white on white," sighs Jo, who was crossing fingers that her second open day a week later would be business as usual.

● Jo Hynes grows many rare and beautiful plants in her large garden. Check out her opening dates in the NGS Devon Yellow Book due out in early March.