Why did the cowslip?
WE have three native primulas in England. Everyone knows two of them, the primrose (Primula vulgaris) and the cowslip (P. veris); both are wonderfully prolific in the wild and easy to grow as garden plants. The third species is the oxlip (P. elatior), which grows only in a small area where Suffolk, Essex and Cambridgeshire meet. Scotland has the tiny bird’s-eye P. scotica, but it’s difficult to grow in gardens.
Primroses are the first to flower; nothing matches their colour or their beauty. Cowslips have an even sweeter scent, whereas oxlips are the hardiest —you see them flecking Swiss meadows soon after the snow melts, when the grass is still brown. All three have a vast natural distribution, as far as the Caucasus mountains and beyond. You can even find primroses in the mountains of Morocco and Algeria. In the eastern Mediterranean, most primroses are mauve, not yellow, and known as Primula vulgaris subsp. sibthorpii. There’s a rare white-flowered subspecies called balearica, too, which grows high in the mountains of Majorca, Sicily and Greece.
Primroses and cowslips are plants of our native woods and meadows. From time to time, people have spotted natural variants and grown them in their garden. The exquisite Primula ‘Gold Lace’, for example, is a mutation of the cowslip, with petals of darkest mahogany tricked around the edges with yellow. It was known and valued as early as the 17th century as a ‘florists’ flower’, grown by amateurs who competed to win prizes for the best specimens. Tulips, pinks and auriculas are other examples of florists’ flowers.
Primroses, too, produce interesting sports and, over the years, many remarkable mutations have been collected and conserved in gardens. ‘Jack-in-the-green’ forms have leafy sepals that form a green ruff around the flower, whereas hose-in-hose primroses seem to have two identical flowers, one inside the other. Both occur in 17th-century herbals and are still available today, as is the elegant doubleflowered primrose called ‘Lilacina Plena’, which has pale-lilac petals arranged like a little rose. I grew it for many years from my grandmother’s garden in Ireland, but, alas, have now lost it.
Our three species hybridise easily, which is where the fun begins. I grow a handsome hybrid between the oxlip and the primrose and I have seen natural oxlip-cowslip hybrids in Spain where the two species grow abundantly side by side. Both are comparatively rare, but the crosses between primroses and cowslips turn up frequently in our countryside. Non-botanists call them false oxlips, which is confusing and explains why it is best to use the Latin name Primula x polyantha. Polyantha? Yes, our garden polyanthas are descended from crosses between the primrose and the cowslip. Everyone grows polyanthas—sturdy, sweetscented beauties—and multicoloured, too, as a result of generations of selective improvement by gardeners and nurserymen. They are the great staple of winter bedding, flowering in mild weather from November to May.
Modern polyanthas have inherited the best characteristics of each of their parents (unlike my children). The strong single stem of the cowslip is a dominant gene, as are the larger flowers of primroses. But you need to look at them carefully because almost all primulas are heterozygous. I first learned that word as a teenager at Winchester—my inspirational botany master Michael Baron will be 90 later this year —and it means the flowers have two forms. Thrum-eyed primulas have their stamens at the mouth of the flower, whereas the pineyed stick out their stigmas. Each can only be pollinated by the other, not their own. It’s Nature’s way of making them crosspollinate, which ensures the continued vigour of the race. Thrum-eyed forms are generally more esteemed by connoisseurs.
Gertrude Jekyll was an early developer of polyanthas as bedding plants. In the 1890s and 1900s, the Aberdeen firm Cocker—later known as rose-breeders—raised a race with double flowers that they prefixed ‘Bon Accord’, the motto of their city. Nowadays, double-flowered primulas are micropropagated by the million, whereas bedding polyanthas are grown from seed. Nurserymen encourage us to treat them as disposable—grow them for a season then throw them away—but I like to split the plants, either in spring or autumn, and spread them around. They are all so tough, so strongly scented and so uncomplaining. I love the way they welcome the bees and spread their hybrid offspring over the garden. Let them naturalise and they will give you endless pleasure. There is never a dud among them.
Charles Quest-ritson wrote the RHS Encyclopedia of Roses Next week Scent
You can find primroses in the mountains of Morocco