Everyone has one of those seemingly indestructible friends. You know, the ones who run marathons in heatwaves, go sea swimming in the depths of winter, and whatever the weather somehow manage to have an enormous, earth-motherly smile on their face while doing it. So, when I was invited to the October wedding of two such friends, held in a gathering of tents in a Welsh forest, where the activities included lake swimming and outdoor log saunas, my poor, tropical physiology was braced for the worst.
However, from the moment I arrived, just as the leaves flushed their autumnal shades, I was overcome by their incredible uplifting power, made all the more intense by the amount of time spent around them – and so jaw-droppingly beautiful that I barely noticed the chill. We gardeners spend so much time fixated on improving the size and quality of flowers, fruit and veg, it really got me wondering what we could do to improve the drama of autumn leaves.
As with pretty much every aspect of horticulture, there are two key factors that determine the quality of autumn colour: the unique genetics of the plant and the cultural conditions you subject them to. While there are plenty of lists out there of plants whose leaves turn bright yellow, orange or red before they fall, the focus on how to further intensify these shades is a little lacking. I think this is a shame, as in theory this should be relatively straightforward.
The yellow and orange of autumn leaves is revealed when the green pigment, chlorophyll, is drained away at the end of the summer. The remaining orangey pigments, known as carotenoids, which were there all along, help fulfil a range of biological functions, including acting as a UV screen to prevent cellular damage. As higher levels of carotenoids are produced by plants grown in brighter conditions, for the most dazzling yellows and oranges simply pick the sunniest possible locations to plant them.
But what about reds? Well, while the evolutionary reason why plants do this is still a bit of a mystery, hotly debated by botanists, we do know how they do it. Created by pigments called anthocyanins, unlike carotenoids these are only triggered into being released as temperatures tumble. So picking a colder spot, ideally without too much wind to blow away the leaves, would give the hottest hues. A great choice for a frost pocket in a sunken area, for instance.
However, the easiest way to enjoy the most fall colour is to make an excuse to get out and see it. Wrap up warm, get your mates round for an autumn barbecue, mix a cauldron of hot toddies and take it all in. The British tradition of standing around an open fire on the hottest day of the year is a little nuts anyway, especially when doing it right now will give you the chance to revel in a natural miracle you otherwise might miss indoors. A lesson I learned from my friends’ wedding this year.
Follow James on Twitter @Botanygeek
