One of the best things about growing in the UK and particularly in the south is pushing the boundaries on just what you can get away with growing. As I look across the garden borders I can see a range of plants that come from all over the world, yet somehow, can survive on this wet, occasionally sunny little island. With Siberian iris planted next to Mexican dahlias all in the shadow of temperate palms, the garden is a horticultural representation of the globe and I want to write about one climate region, the tropics.
While its relatively easy to grow plants from hotter areas such as the mediterranean, southern Europe and southern US, where temperatures can still dip below zero, it’s much more difficult when it comes to the tropics as plants native to these climes are almost universally frost tender. They either need bringing indoors for the winter or may tolerate a very brief freeze (but won’t be very happy about it). Other tropical plants will be killed by frost but as they grow from bulbs or rhizomes, they will come back the next season if that bulb or rhizome remains relatively dry and unfrozen through the winter.
One of the most exotic plants we have planted out in the garden is a Kahili Ginger, or Hedychium gardnerianum, also known as a ginger lily. Like several other plants, this one is actually Madeiran and came from a division of the parents’ original, which they bought as a rhizome while we were on holiday a couple of years ago. It grows fleshy alternate-opposing leaves on thick sturdy stems atop which grow the flowers.
We received our division in Spring this year, long before the corner border was even started and so it spent a couple of months sheltered in the greenhouse in a large pot.
The division was two stems and a chunk of rhizome with a mass of long, stringy roots. As Spring got underway and the weather warmed up, the ginger joined the Nomadic Patio Pot collection while we worked on the border where it would eventually be planted. It was potted up in rich, fertile soil as these plants are heavy feeders and that triggered several shoots to emerge from the base, I think there were around ten in all. By the time the border was finished and ready for planting, the ginger was bursting out of its pot and the shoots had grown into thick stems.
As the summer wore on there were no signs of flowers, just more and more leaves and stems. It was high summer at the end of July, when the first flower buds started to appear. Initially, they look like some scaly wormy thing.
These then unfurled and opened out over the course of a few weeks:
From these “tubes” emerge bright yellow flowers with striking, long red stigmas and of course, that powerful sweet scent that hangs in the air on hazy summer evenings.
The flowers don’t last for very long and in a single flower spike, the flowers at the bottom can already be starting to fade as the newest ones at the top are opening. It’s just as well there are so many stems. The rule is one flower spike per stem and no stem will flower twice. Once a stem is done flowering, its leaves will carry on feeding the rhizome but it will produce no more flowers, it won’t even branch new shoots.
This ginger is hardy, rather, the rhizome is hardy as long as it doesn’t get too wet over winter and it doesn’t freeze. When we come to protecting this plant for winter we will allow the stems to die back and cut them down to the ground, then we’ll cover the crown with a thick layer of mulch and probably pin down some plastic sheeting over the top to keep the rain off. Despite the garden being very wet (generally) I’m hoping that with the corner border soil level so much higher than the surroundings, the water will drain away quickly and keep the rhizome from rotting.
As an insurance policy, we also have two “seedlings” of this ginger that were grown from the seeds of the original parent when it flowered last year. Those seedlings are very bushy, very vigorous and are currently protected inside the house as their rhizomes won’t be established enough to survive outside yet. They will need to be planted outside next year though, somewhere.
Kahili ginger is a vigorous, bold, architectural, exotic plant and the flowers are a showstopper with a scent that carries on the breeze. If we’re successful with our winter protection, we’ll definitely look forward to seeing it at the centre of the exotic border next year. For us, it also has sentimental value given its Madeiran holiday heritage. I couldn’t ask for much more, really.