Garden of Indigenous Plants

Garden of Indigenous Plants

by Rob Reid
(Photographs of Rob's garden can be seen here.)

(Click here for a discussion of the importance of gardening with indigenous plants.)

Click here for The National's article "Gardening with the natives" published March 21, 2009.

There can be few countries around the world which have escaped the influx of people from elsewhere. At the one extreme were the colonizers from Europe and elsewhere, but with the late 20th century globalization came easy long-distance travel by foreigners either visiting or coming to stay. With these influxes, of course, came a flood of ideas imported from the country of origin. Settlers in a strange place feel comfortable with what is familiar, and trees, shrubs and garden plants were brought in to satisfy this desire for a home-from-home.

Local people, finding either new uses or perceived prestige in the imports, adopted and spread these foreign plants, encouraged often by a natural lack of appreciation for what has always been familiar and plentiful.

The problems of these foreign imports are well known, ranging form the potential for major disruptions of the local ecosystems and uncontrollable invasions of the indigenous vegetation, to a wasteful requirement for constant special care.

To put it the other way around, the value of encouraging the use of indigenous plants in gardens and parks goes beyond the aesthetic value that many of us place on maintaining the distinctive local flavor of a place, to the support of the undisrupted complexity of the ecosystems outside of the garden or city limits, and more efficient use of resources like water and soil fertility.

When I came to Al Ain, I was fortunate to rent a house which was new, unfinished and set in large grounds which had not yet been paved from wall-to-wall with cement paving stones. Building rubble is not cleared away here, but covered by a layer of red dune sand. The wind immediately set about redistributing this sand, anti-clockwise around the building. If the front and back doors were both open, the sand took the short cut through the house, and many were the days when we returned home and “helped’ the dunes back outside! After a few back-breaking weekends with a shovel in my hands, I decided to let the elements have their way, and stood back to see where the wind would build the dunes, and where it would leave me a gravel (builders rubble!!) plain. After a couple of months, I gratefully accepted the free landscaping service, and proceeded to plan my garden around these features.

The back-breaking work was only beginning!

I had determined, (as I had done before in S. Africa), to lay out my new garden using mainly indigenous plants, and set about locating some of the commoner species. Putting in the trees first has the great advantage of giving these feature plants an early head start, and providing a guide to the development of flower beds and other smaller features later. All went well at first, and the Ghaf and Sidr trees went in, in natural-looking groupings, and in places where I wanted shade or a strong height dimension. The large central area of the garden was to be retained as a natural-looking desert, and anything which seeded itself was welcome.

Then the trouble started, as I realized that most indigenous plants, even the ubiquitous Samr tree (Acacia tortillus) and dirt-common Aerva javanica are unobtainable commercially. There followed 15 months of self-consciously and surreptitiously sneaking around road verges, servitudes and derelict properties, finding and digging out baby plants of the species I was looking for! Time-consuming failures taught me the technique necessary for each type of plant, depending primarily on the type of root system it had, and the soil/gravel I was dealing with. I learnt that a baby Salvadora persica (toothbrush bush) growing under street trees was likely to have a massive woody root system because the parks workers had spent years cutting it back to ground level during cleanups! I learnt that a Samr seedling 15 cm long probably had a tap root already 3 times that length! And I learnt that even simple tap root systems do not necessarily grow straight downwards, even in soft sand. I learnt just how much water to add to each type of soil to hold it together around the roots, and that if you managed to get the plant out intact on the blade of your shovel, you needed to take it home just like that, rather than try to transfer it to a pot or a packet. That limits you to one plant per expedition!

Creation of a garden requires consideration of 3 main areas:

1. Landscaping
2. Choosing and growing the right plants, and
3. Maintenance

This is the planning (or re-planning) of the layout. An indigenous garden is, more or less by definition, one which acquires a natural look, and such a garden does not sit well with the artificial formality and symmetry of a Greco-Roman or Victorian style! There is a strong tendency in the Middle East to lay out grounds with a predominance of straight lines and squares, and a clean, manicured look. If this is your preferred style, then read no further!

Landscaping implies the process of planning the layout of the area, and the first element to be addressed is the third dimension, consisting of the topography of the ground, and the taller plants (trees and shrubs).

The second element is color, and this is the part which is usually given the most attention. However, don’t forget that color does not only emanate from flowers, but just as importantly from foliage, which can come in a wide range of greens, grey-greens and yellows. Finally, and especially in this area where strong massed color can be difficult to create from indigenous plants, do not forget the impact of textures, both from mass planting of one species and from creating strong contrasts with well-chosen different species.

If you have a slope to deal with, this can be used to add interest. However in generally flat Al Ain, even the shifting sand can help create some differences in ground relief.

Most of the third dimension in the garden comes, of course, from the trees, which can be grouped or single. Grouping several individuals of one species together enhances the impact, as the color and texture will be uniform. They can be irregularly scattered for the natural look, and at various distances from each other. Remember that nature does not deal in straight lines, rows and grids!! I interfere as little as I can with the natural shape of my trees as they grow. For sure, there is no place in this type of garden for lollipops, corkscrews and other weird geometrical shapes!!

These can be used in a mass to fill in a large barren area, to make an understory between trees, or to give shape and focus to a flower bed. Again, massing one species together is often the best way to go.

Beds of forbs (flowers and small shrubs, to you and I!!) is the way to give the garden pleasing shapes and divide up the garden into areas. Edging these beds is a challenge here – at home one would simply remove the grass, leaving the required shape within the lawn. I have used several different materials to edge beds, from blankets of white stones, to triangular chunks cut from the bases of palm fronds, and dry-laid cement pavers. All have done the job I wanted. In general, I mass one plant species in one bed, to create an impact and make the bed shape more noticeable.

It is not my intention to bore you with lists of local plants which you can grow. I have used Marijcke Jongbloed’s outstanding book as a guide. Growing plants easily and seeing them do well means growing what is adapted to your local environment, so remember that “indigenous” to the Emirates does not necessarily imply “indigenous” to Al Ain. Here the gravel is alkaline and rich in calcium, for example, and the plants you see growing wild here are able to do well in these conditions. The commonest plants will generally signify the toughest, and that is a good place to start!

I have grown Aerva javanica extensively, as it grows easily and looks beautiful in a big mass. Once you have some in the garden, they will seed themselves all over the place, so the awkward problem of getting hold of the plant soon goes away! Heliotropium kotschyi is also very worthwhile, and although Zygophyllum mandavillei does not have a noticeable flower, it grows easily in either gravel or sand, and adds a bright green contrast; you do not even have to irrigate this tough little bush!

Whatever it is that you want to grow from the riches of the local desert, you will probably have to find them and dig them out yourself. This is where your dedication and resolve will be tested! These plants may survive extreme heat and water deprivation, but they do NOT like their roots disturbed!! Transplanting them successfully therefore involves finding baby specimens, preferably growing in sandy places; it involves skill in getting them out with the sand around the roots intact; and it involves having a thick skin, since if you are noticed, on your hands and knees pouring water onto tiny desert weeds and wielding trowels, packets and pots, you will attract some very puzzled and scornful looks!!

Whatever it is that you want to grow, you will have to learn what its root system looks like first. Most local plants have a tap root, which is a simple root heading straight downwards, without many (or any) visible adventitious (side-branching) networks. The problem with these is that the sand/soil does not adhere around the root well when it is disturbed. And it can be a challenge to get beyond the bottom of it, even in a very small specimen. I have had the best success using 2 trowels or 2 shovels together, and transferring the plant directly home and into its waiting hole, without the use of a pot or plastic bag. If you do use a pot, you must wait a few weeks before transferring into the garden, so the soil in the pot becomes sufficiently compacted.

I tend to lose interest in a garden once it reaches this stage!! The creativity is all done, and the donkey work is left! If you have planned carefully though, this should be the time you can sit back and enjoy the garden as it grows and matures, without a great deal of regular work to keep it going. It is important to provide each type of plant what it needs, and there is a whole spectrum of requirements, even for plants from an apparently uniform desert environment.

Provision of water is, of course, the most obvious element. Even in a desert, some plants tolerate more water than others. The trees are going to need a good water supply as you cant predict whether any individual in a particular position is going to get its roots into the water table or not, or how soon. They also need a helping hand when they are small, of course. Some plants tolerate water and grow faster, while also managing perfectly well without it if need be. Some, like Oleander, even require it, as they grow naturally in water courses. Calotropus is a good example of a plant which is happy with extremes. I have a specimen which germinated naturally, at the beginning of summer, in powder-dry sand, and never saw a water molecule until it was a meter high, when I could no longer bear to stand on the sidelines and watch this incredible display of arid defiance and provided it with a drip nozzle! Its growth rate did not change one bit, and it continued onward and upward exactly as before!!

Gardening is always a work in progress, and a garden is never done and completed. In a moist climate there comes a time when the work suddenly changes from trying to make things grow, to trying to stop them taking over! I doubt if that ever happens here, but there is certainly a continuous journey of creativity and change waiting for those who enjoy it.

While it is true that the concept of indigenous gardening involves the use of desert-adapted plants, it is also true that most desert plants will grow better, flower better and end up bigger and more robust if they are not constantly water-stressed. This is what gardening is all about – helping the plants to reach their full potential and to look good, and many a scruffy plant which is hanging onto life “by its finger nails” in the desert will surprise the gardener when it is grown in a garden and cared for. Here, as in other similar environments, some plants which do well in the desert are obligate xerophytes, and will not tolerate much more water or less heat. Others are simply tolerant of the harsh natural conditions to the point where they can out-compete those that are not, but will do better if conditions are better. Others, especially the trees, reflect the invisible presence of ground water, and have long and robust tap roots which can utilize this resource.

Whether laying out a completely new garden or re-landscaping an established one, it is advisable as far as possible to start with a plan. This allows for the logical setting out of the irrigation system. There are 2 possible approaches:

• The “geographical” approach, whereby all the trees and plant beds closest to a given valve/tap are supplied by that valve, allowing maximization of the available pressure and saving on pipe length.
• The “botanical” approach, puts all specimens of a particular species, or several species with similar water requirements, onto the same pipe circuit from the same valve/tap. This allows easy control of the amount of water, and for the watering regime to be tailored to their needs, and changed with the seasons.

If the garden is small and the water is sourced from one valve, then the above approach allows for different pipe runs to be separated from each other by the use of in-line taps, giving the same control.

These irrigation systems are very easy to change, add to or close down, but the pipes should be buried to at least 15 cm, as few plants enjoy a blast of boiling water as watering commences! Besides, a spider web of black piping is not attractive. Thus a plan drawn on paper will save much head-scratching later when the layout has been long forgotten.

Basic requirements for a hassle-free garden include a dedicated pump, which is switched by a timer device allowing at least control over duration, frequency and times of watering. Do not be tempted to take short cuts here, as at best you will become a slave to the daily maintenance of the garden, and at worst you will become unable or unwilling to apply the necessary regularity yourself and end up with struggling or dying plants.

You will also need enough water in the tank. However, a word of warning – sprinklers, which are necessary for lawns and expanses of ground cover, use vast amounts of water very fast. Drippers and nozzles, on the other hand, use surprisingly little, and put it only exactly where it is needed.

And you will need valves/taps, several if your garden is large, at intervals down-stream of the valve and around the periphery of the property, in order to maintain the pressure at the farthest point from the pump.

It makes sense in a desert climate to water late in the day or at night, to minimize evaporation and slow down the drying of the soil. Watering times should be tailored to the season. In mid summer and through winter, the best schedule is to water deep but more seldom. Increase water in frequency and amount only when the plants show signs of starting to grow actively (March and September). It is generally better to water deep, less frequently. This minimizes evaporation, and with it, helps prevent the raising of dissolved salts to the surface and building up a saline deposit there which many plants cannot handle. Remember too, that the roots of the plants are generally deeper than you think – it is no use wetting the surface sand if the roots are not getting it.

A well planned irrigation system takes much of the drudgery out of gardening and leaves one free to enjoy the creative aspects. However irrigation drippers and pipes do go wrong, and each connection and each dripper needs to be inspected and re-adjusted fairly regularly. If you wait until a plant tells you there is something wrong, it is often too late. Although these plants are drought resistant, if they have been grown with a regular supply of water, they will usually have grown much bigger than their wild relatives, and will have become less resistant to their water being cut off.

The botanical names in this article have not been checked with keys or herbarium, and it is possible that some of my ID’s are not correct. Anyone who is inspired to try his/her hand at this type of gardening, or simply has the curiosity to see what it is that I am “on about” is most welcome to visit my “patch”, and I will help with whatever knowledge I have to offer. I can be contacted through the ENHG or on email at rreidsa@gmail.com.