Sub Tropical Gardens

Are we getting warmer or is it me?
asks Dr DAVID SEYMOUR

SUB-TROPICAL gardens were very much in fashion throughout the latter part of the nineteenth century and into the early part of the twentieth century with the fashion only coming to an end during the First World War. There has been something of a revival of interest in this form of gardening in the last few years although whether the new gardens are authentic or not will be debated over at length by those who know about these things, and by those who do not.

This short article is about sub-tropical plants that will grow here in London. Most are really temperate subjects that look sub-tropical, but some are the genuine article that will usually stand a mild winter or at least will survive if given a little bit of protection.

The illustrations that can be found in many old gardening books tend to show sub-tropical gardens in a very stylised form. That is, they usually show large leafed or spiky plants sparsely and evenly spaced out on a lawn. More often than not with a lady, with a bonnet and bustle, and gentleman with a top hat and frock coat, seriously admiring them.

Sub-Tropical Bedding

This type of gardening was often called sub-tropical bedding, which indicates the effect was achieved with tender plants that had been over-wintered in a greenhouse and planted out in early summer. Even William Robinson, not noted for his cheery happy-go-lucky attitude where bedding was concerned, was a fan of the sub-tropical kind; he even devoted a book to it. He advocated the use of cannas and caladiums in the tall centres of flower borders. This type of border never died out but is now mostly seen on traffic islands, without the caladiums.

A good example of sub-tropical bedding can be seen in the summer months at the RHS Garden at Wisley. Their border tends to be made up mainly of tender flowering plants, with the odd big-leafed plant evenly distributed throughout to give that 'exotic' feel. It is very colourful, but looks (to me) like a garish herbaceous border. They also have two monocot borders and a grass garden, all of which are made up of hardy plants that could add to the illusion of tropicality.

Another good hunting place is the Temperate House at the Royal Botanic Gardens, Kew, which is full of good plants that will grow (but not all) in the open all year round in the London area.

Creating The Illusion

It is from these examples that some effective sub-tropical border plants can be chosen. As the UK is not in the sub-tropics, it is best to choose from what will grow here, supplemented with a few carefully chosen true sub-tropicals that have been bedded out. This way we can create the illusion, at least for a few months, of a sub-tropical garden, and possibly longer. The idea would be to grow plants that will survive the average winter in London, and forego as far as possible any overwintering, thereby giving the illusion of a sub-tropical garden.

One 19th Century practice was to plant sub-tropical subjects on top of a raised bank made up of brick rubble. The idea being that summer heat would be trapped by the brick and released slowly when it was needed. This seems to me rather a triumph of hope over experience, but is worth trying and the increased drainage can do no harm.

What should a sub-tropical garden look like?

A riot of hot colours in the manner of Christopher Lloyd, or green-leafy-packed-in-tight, more tropical than sub, in the style of Miles Challis? More of a sub-tropical wild garden perhaps. Angus White of Architectural Plants has coined the term 'Big Leafism,' and this is the way to go, i.e. big leafed mixed with spiky stuff and all crammed in.