I’m not a climate expert, but I don’t see the UK becoming tropical any time soon! I take global warming very seriously and the human race’s impact on the climate and environment. Anyone who doesn’t is an idiot, frankly. Knowing what we know, technology has to come into play where we work with our environment rather than pollute it further.
But global warming is a relatively slow process. We can’t reliably say that in the UK in the immediate future, we are going to have a climate warm enough to easily grow tropical plants. My understanding is that our weather is very much subject to the jet stream. What happens to that jet stream is influenced by rising temperatures around the world at different points. The net effect at least in the short term is that it’s not necessarily getting that much warmer. Though we have just had a warmer, drier summer than usual, we’ve also had extremes of cold and rain lately.
"Plants might be indigenous to other areas of the world, but mankind can migrate them. Plants are very adaptable!"
To start thinking we can suddenly easily grow tropical plants – we’re in danger of suddenly getting a major cold snap and then all your plants turn to mush. But can we adjust our gardens to be more tropical? Yes we can, but we have to be aware of the setting.
If you’ve got a protected garden that’s south facing in an urban or city environment like London for example, where you’ve got a warmer microclimate by two or three degrees than the surrounding countryside, and you take appropriate protection in the winter, to fleece and protect tropical plants, it’s perfectly feasible to grow more tropical plants – the more robust they are, in other words, the more extreme cold they can take, the better. But you have to do your research and you have to be mindful of the conditions.
Plants might be indigenous to other areas of the world, but mankind can migrate them. Plants are very adaptable! Roses and rhododendrons for example are both considered very English plants – but they’re not. We imported them from China. You see the red rose on the rugby shirt – but it’s not strictly English. We imported it during our Empire days and it grows very well here. I love using tropical and sub-tropical plants, more of the latter really. Palms and plants that come from Mexico, South Africa, etc.
"I’m looking to get more plants in from South Africa because they have similar conditions there, but the plants look so fantastically exotic – and almost alien."
There are a lot of plants that look tropical that you can already grow in your garden – your cordyline, agapanthus, trachycarpus, Chamaerops humilis, the yucca family – the hardier versions, like yucca rostrata and yucca gloriosa. But again, even though they’re hardier, you’ve got to make sure they’re in a free-draining situation – they don’t like their toes in water, so sharp draining is good. However, the trachycarpus chusan palm is perfectly happy on the beach for example where they’ll get some salt water, but it doesn’t bother them. Some plants come cope with quite extreme conditions.
I’m looking to get more plants in from South Africa because they have similar conditions there, but the plants look so fantastically exotic and almost alien in some cases because we’re not familiar with them. A lot of plants that we’re familiar with now were actually imported from around the world. There are some extraordinary plants out there. But it’s all about the care and understanding of what the plants need if you want to grow them. It’s not just the temperature, it’s the soil conditions and the make up of the soil – the PH levels etc.
It’s also quite easy to grow edible plants that don’t grow naturally here in the UK – well, we’ve always had greenhouses, it’s nothing new. It’s just dropped off a bit. Citrus are perfectly happy here – you have to be a bit careful about the cold though. But you can put heaters into greenhouses and make sure you have good insulation for the winter. That pulls an awful lot more plants through the winter and makes your choices much more exotic.
The Victorians really researched this greatly with their big glasshouses and exotic gardens. The Lost Gardens of Heligan were renowned for bringing in tropical plants – they have pineapple pits for example.
I had a client in Guildford recently and we put in a glasshouse there with underfloor heating with citrus, pineapples, gourds, kiwi, chillies and peppers. I think kiwi actually can survive outside here too. But you don’t have to have global warming, a big glasshouse or even a garden though to experiment and be successful with more tropical plants – you’ve always got your windowsill too.
Philip Nash is Landscape and Garden Designer at Nash Garden Design