1 Dec 2019

The Great Glasshouse in Winter – South Africa

Bruce Langridge

As part of a series of blogposts looking at Great Glasshouse plants in flower in winter, we now take a look at flowers from the Cape Floristic Region of South Africa.

The Cape is the most floristically diverse place on Earth and not surprisingly, our display is a real hit with visitors. But is it worth seeing in winter? This week we sent out our conservation volunteers to make a count of all the plants in flower in our South Africa display and they’ve come back with a list of over 40 different species of flowering plant.

Now bear in mind that this has been considered one of the most dormant times of year in the Great Glasshouse and this suddenly becomes a surprisingly high figure.

So what plants are in flower?

For me the outstanding plant is one of the smallest. The turquoise flowers of the Cape cowslip Lachenalia viridiflora are gorgeous and having only just being discovered in the 1960s, it is now restricted to just one locality on private land on the Cape west coast, where threatened by the construction of holiday homes.

You’ll find this in the display bed next to the Western entrance – the recent introduction of new soil and compost here has given this patch a really fresh look.

There are 8 species of Erica heather in flower to start with, including the beautiful pink tubular flowers of Erica discolor –  the curve of the flower tube matches that found in the pollinating sunbird’s bill. Now bear in mind that the UK has only 4 native Erica species of heather, the Cape has over 800 Erica species, 690 of which are found nowhere else on Earth.  A recent scientific paper suggests that all Erica species on the Cape can trace their evolutionary roots to one common ancestor 15 million years ago.

90% of the world’s pelargoniums come from Southern Africa and we have three species in flower at the moment – all with different intensities of red in their bloom. One of these, the Cape pelargonium Pelargonium sidoides, was used by Zulu people to treat lung problems and before the advent of antibiotics, the roots of this plant were used to treat tuberculosis patients in the UK.

Proteas are possibly the most distinctive plants of South Africa and their national flower, the King protea Protea cynaroides is just about still in flower today.

It’s worth stroking the big, heavy flower head – it’s surprisingly soft.

A couple of other plants stand out. The unusual flowers of Hymanthus albiflos, a coastal plant on the Cape, has led to its English name of paintbrush or shaving brush flower.

But I prefer Kniphofia bruceae, not just because it shares a name with me. Originally described over a century ago, it was thought to have become extinct in the wild until a lone plant was discovered in its native South Africa, surrounded by a plantation of alien Pines.

But it’s soon to have a rival – the buds of the tree aloe Aloe arboresecns look like they’re soon to burst, possibly revealing their spectacular red blooms in time for Christmas.