How many Botanic Gardens do you think there are in the UK?

And how many of those can you name?

The first question is a bit vexed: it depends, you see, if you count pinetums and arboreta, and gardens with botanical add-ons like herbaria. But let’s leave all those out and just concentrate on the gardens with ‘Botanic’ in the name. There are around 25 of them.

Now – how many of you can name all 25?

Well, most of you will have Kew on the list, and probably the Edinburgh Botanics (three gardens, really, though we’ll count them as one) and the National Botanic Garden of Wales. A few might have remembered Ness over in Liverpool; and the Oxford and Cambridge Botanic Gardens.

That’s six.

But give yourself a pat on the back if Paignton Botanic Gardens was in there; or the St Andrews Botanic Garden in Fife, or either of Manchester’s two Botanic Gardens, or Birmingham’s for that matter.

The fact is that the vast majority of our botanical treasures are kept in small, obscure collections. Many are attached to and funded by universities: we all know the precarious financial states many of our universities are in, but worse, the future of the study of botany at university is in doubt too. Only Bristol and Reading Universities offer an undergraduate degree in pure botany – even though it’s the one degree these days which all but guarantees you’ll get a job on graduation.

We’ve never needed botanists more, what with biofuels, food security and the loss of more medicinal plants than we will ever know existed. And if the student botanists go, so do the botanic gardens. The Firs Botanical Grounds – a series of experimental gardens and glasshouses bequeathed to the University of Manchester in 1922 – is already on its way; its gates closed, almost without comment, this summer.

There’s another layer of botanic garden which is funded largely by local councils. It’s a bit of an anomaly in this day and age to have gardens kept mainly for the study of plants and paid for from the public purse, and it’s about to become a thing of the past, too, as botanic gardens are – perhaps rightly – seen as an extravagance at a time of five-figure budget cuts. They tend to get mixed up with parks, even though there’s a world of difference between the two and botanic gardens are far more expensive due to actually having plants in them (and usually ones requiring costly specialists to tend them). So they’re a soft target.

St Andrews Botanic Garden, Fife, Wavertree Botanic Park and Gardens in Liverpool and Southport Botanic Gardens on Merseyside, the Fletcher Moss Botanical Garden in Manchester, and my favourite Botanic Gardens of all, the Ventnor Botanic Gardens on the Isle of Wight. All council funded; and more than one, as a result, now fighting for their increasingly unlikely futures.

You could be callous about whether we actually need 25 botanic gardens, I suppose; it is quite a lot for one small and rather overcrowded island off the coast of Europe, after all. As gardeners, we tend not to like botanic gardens that much: too much science, not enough prettiness.

But as gardeners we also adore plants. And whatever you think of them as gardens, botanic gardens hold some of the most extraordinary plants you can imagine.

There are botanically important collections: Ventnor Botanic Gardens has the country’s leading collections of southern hemisphere plants. And historically important individuals: there’s a Chusan palm planted by Queen Victoria at Ventnor, and what, I wonder, has happened to the 80-year-old cactus in residence at the Firs Botanic Grounds?

In the headlong rush to save money it’s sometimes forgotten that botanic gardens are also living museums: the plants they contain are woven into our gardening history. We’ll all be the poorer if they’re consigned to the ‘surplus to requirements’ box in Town Hall treasuries.