It’s daffodil time – don’t you just love ‘em! Their appearance is always a cheery signal that spring has arrived.

If you adore daffodils in their many varieties, the RHS asks you to be a daffodil spotter as the basis for scientific research: I’ll come to that later.

Daffodils belong to the plant genus narcissus, all of which have a central cup or trumpet surrounded by six petal-like tepals. (The term “tepal” is used when these parts cannot easily be classified as either sepals or petals.)

Generally we call a plant a “narcissus” if its central cup or trumpet is small, or a “daffodil” if it’s large.

Daffodils are native to meadows and woods in the Iberian Peninsula and North Africa. From the early 1800s daffodils became hugely popular in Britain and were being deliberately hybridised to create new forms and colours.

The bright yellow daffodils decorating our gardens, roadsides and parks are usually garden varieties, of which there are thought to be hundreds of varieties found in the UK. To see a true wild daffodil you’ll need to head to a woodland or damp meadow in North or South West England, or Wales: wild daffodils have a two-tone look – the trumpet is a darker yellow – and are relatively short, forming clumps carpeting the ground.

The RHS holds the register of known daffodil cultivar names bred around the world. It says there are 31,000 cultivars of daffodil, organised according to 13 different types, including trumpet, double and split corona daffodils.

The RHS is now asking industry and gardeners to help it map the UK’s daffodils and locate three rare or historically significant varieties.

It has launched Daffodil Diaries, a web page where it asks people to log where daffodils are blooming in their area, alongside basic information such as colour, type and height. Scientists at the RHS will use this information to understand environmental influences on plants, buyer preferences and their spread.

The call to action comes as the RHS celebrates one hundred years since its scientist James Kirkham Ramsbottom was honoured for his work in developing a hot water treatment against eelworms which saved the daffodil.

The treatment remains a standard precaution in bulb production today. You can see the original copper boiler that administered the hot water treatment in the museum within The Old Lab at RHS Garden Wisley.

The three daffodil varieties the public are being asked to look out for, selected by the RHS and the conservation charity Plant Heritage, are: “Mrs R.O. Backhouse”, one of the first pink daffodils, with a solid coral pink trumpet and ivory flowers; “Mrs William Copeland”, a white, double-flowered daffodil; and “Sussex Bonfire”, a double-flowered yellow and orange daffodil bred by an amateur breeder from Sussex.

Locating these will help aid their survival and may even enable the preservation of genetic material for future breeding, particularly as our climate changes.

Information and images of daffodils thought to be the above varieties should be submitted before 4 May via the Daffodil Diaries page on the RHS website www.rhs.org.uk/science/daffodil-diaries

Daffodil fans mustn’t miss a Daffodil Show to be held at RHS Garden Wisley on 8 and 9 April, when you can see more than 100 classes of daffodils showcasing their range of size, shape and colour. The event is free with normal garden admission.