Do plant names really have to keep changing?

I speak to garden groups all over the country. And the question on the lips of so many gardeners is ‘why do plant names need to keep changing?’. I oft hear the cry “I’d only just learned that plant name and now it’s been changed!”. So, the big question is. Who is making these changes? Why are they making them? And frankly, who said they could mess around with our plants anyway? To compound the issue, a little like Opal Fruits and Cat Stevens, growers, nurseries and plant catalogues often continue to list plants under their old name! It does make commercial sense. If one of your best sellers is Gaura and you know your customers will be looking for it under the ‘G’ section of your catalogue or plant stand, why would you suddenly list it under its new name, Oenothera, which most gardeners are yet to embrace?

As a so-called garden expert, I have no option but to adopt these new names but it’s a pain for me, too. Hylotelephium hardly trips off the tongue compared to its former, dare I say catchier, name Sedum.

It might surprise you to know that this process of plant names changing has been underway for a couple of decades. It might also be a relief to know that the botanists making these decisions have nearly completed their dastardly deeds! The reason for the name changes is all down to DNA. Historically, plants were named under a system developed by the botanists Benthem and Hooker. It was a nice simple system.

Plants were grouped together into their families and genus (surname) based on visual observations of their, erm, sexual parts! By that I mean the number of stamens, petals, etc… that their individual flowers were composed of. For example, plants in the Rosaceae family have their ‘parts’ arranged in multiples of five. Stay with me here. Meaning that roses, mountain ash, strawberries and apples were all grouped together under the family name Rosaceae because each one displays ‘parts’ in series of fives. The big change came when humans learned how to sequence and understand DNA.

This recent set of changes to our plant names is because today, rather than being grouped by ‘sexual parts’, they are grouped by DNA. There is a very sound logic to this. And of course, DNA is absolute, meaning that the changes will be permanent. Much as we might struggle with calling Dicentra its new name of Lamprocapnos (catchy, hey!), it's here to stay.

So, to answer the question: Why do plant names have to keep changing? It's simply that some of our historic observations of ‘parts’ were not wholly accurate. DNA is undeniable. The good news though is that the process is nearing its completion. The group of botanists working on this project are known as the Angiosperm Phylum Group (which sounds like the offshoot of a dodgy cult) and have completed the renaming of all the monocot plants, in other words, all the grasses, bulbs, palms, gingers and bananas. They will never change again. And they are well through DNA sequencing and renaming (where required) the 175,000 broadleaf plants on Earth.

Re-naming helps further our understanding of plants, their evolution, their relationships between one another and their distribution around the world.

So, the driver behind all these changes is essentially scientific accuracy. Which while being frustrating at times, helps further our understanding of plants, their evolution, their relationships between one another and their distribution around the world. It does mean we’ll need to embrace new language and new names while kissing goodbye to some names we loved, but ultimately, we’ll have a settled list of plant names that won’t change again.

And while I’m braced and ready to begrudgingly accept this, Starburst can take a run and jump – they’ll always be Opal Fruits to me!

Get in touch:

Want to share your views on changing plant names? Email us at: letters@gardenersworld.com

Read more:

• Gardening for beginners: Botanical plant names
• Why do plant names change?
• Botanical names quiz: royal plants