Vachellia xantholophaea: Is this really the best choice for my small garden?

Many of us will recall the words from Rudyard Kipling's story of The Elephant's Child, who was told by the Kolokolo bird to  'Go to the banks of the great grey-green, greasy Limpopo River, all set about with fever-trees,....'. 

Why Fever tree? It was a common occurrence for early travelers and pioneers to contract a bad fever when traveling through areas where the trees grew and the trees were thought to be the cause of the fever. The fever of course was Malaria. In a cultural twist, the bark of the trees was traditionally used by the indigenous population to treat fever.

This then, is the home of the Fever tree. Hot and dry in winter, hot, wet and humid in summer. Here they are in their element, soaring up to 25 meters high with a spread of 12 and more meters across, invariably living near a source of summer water. In winter, the pans in which they often stand dry up, the rivers and streams on whose banks they grow, recede to a trickle and the trees take their winter rest. 

If you have a large garden where you have space to plant a wide variety of trees and you can plant a Fever tree a distance from your living area, you probably don't need to read any further.

If your property is less than 1 000 square meters, read on. Going on the assumption that you have limited space and can only plant 2 to 5 trees in your garden, you need to choose carefully. Remember you have to live with the tree for years to come.

Let's consider some of the facts as they relate to a city or town environment.

All Vachellias have a tap root so the automatic assumption is that their roots are therefore not invasive. On the whole this is true.

However, all trees with tap roots also have a network of sub-surface roots, some larger than others, that are utilized for water and nutrient supplies. The Fever tree, being a water thirsty tree, has a more vigorous sub-surface root system than many others and as it ages, these become thicker and stronger, and also travel a great distance from the tree. Shallow watering may result in some of the roots developing close to the surface of the soil, which could cause a problem in later years.

In its natural habitat and presumably in urban environments, Fever trees are used by some bird species for nesting as the thorny branches provide security Other birds are likely to make use of the tree for perching or resting. Insect eating birds will come to feed but the tree has nothing to offer seed, fruit and nectar eating birds.

I have had a few queries about this but was not able to find any concrete examples or reports of whether the trees are suitable for container growth.

Growing trees in containers causes the plant to become in effect, a Bonsai, albeit quite a large one, so I researched the use and suitability of the Fever Tree as a bonsai. All the sites I found that even mentioned using the tree as a bonsai indicated poor results. Almost all attempts to grow the tree in reduced size failed and those that were initially successful died within a couple of years at most.

My impression is that it may grow in a container for a few years but will not sustain this growth once it has become pot bound.

Once again, if your space is limited, look a little further.

There are dozens of smaller, indigenous, non-invasive, wild-life friendly trees to choose from. Trees that provide an all in one attraction: nectar bearing flowers for sun birds and butterflies, fruits for the fruit and seed eaters and the insect eaters will arrive to feed off the insects attracted by the flowers and fruits. If you choose a specimen from your own natural region, you will have some added advantages: it will be water wise, it is already familiar to the wild-life and, as it does not have the stress of adjusting to an unnatural climate, it is unlikely to suffer from pest infestations or disease.

Please, don't get me wrong. I have great respect for the Fever tree. I would love to have one in my garden. I even tried.  I bought into the hype.  It wasn't successful. I mulched and watered and protected it as best I could through our dry summer. It looked better after the autumn rains. Then I turned my back on it for a couple of weeks, we had a berg wind and the next time I looked I had a stick.