by John A Davies • GDN • 12 June 2010
It was a pleasure to be greeted by a group of exotic palms, undergoing trials at the Agricultural Affairs Experimental Station, Budaiya.
I was there on behalf of the Works Ministry, seeking help in obtaining connection details for tapping into a treated sewage effluent (TSE) transmission line to serve the irrigation system for the Shaikh Isa Sports City.
Readers are probably aware of the government’s campaign to reduce Bahrain’s reliance on the aquifers in favour of treated effluent.
At the beginning, there was some resistance to its use, though this has become less as the benefit to agriculture has become apparent, not least because of the level of its purity, which is the highest in the region.
While it is used mainly for agriculture and urban landscape schemes, its value is becoming appreciated by designers of residential developments.
The use of TSE augers well for the aim of the Municipalities and Agricultural Affairs Ministry to develop Bahrain as a garden – The Garden of the Gulf.
It will go a long way to assisting in the re-establishment of the wide variety of ornamental trees that could be found in Manama 25 years ago, when I first visited Bahrain and which have since mostly disappeared from the urban scene, at least, owing to the increasing salinity of irrigation water.
The predominant ornamental trees in flower at the time of my first visit were Delonix regia (Royal Poinciana) and Peltophtum inerme (Yellow Poinciana), which together provided a riot of red and gold, particularly in the Gudaibiya and Adliya areas.
Salmaniya Park, I recall, was like a botanical garden, such was the impressive range of trees growing there.
These included Cupressus sempervirens (the Pencil or Tuscan Pine) – a coniferous tree commonly found in Mediterranean countries and Araucaria araucana (The Monkey Puzzle Tree), native of Chile.
These have long since gone from the park, due it is said, and as already mentioned, to the increasing salinity of the irrigation water, though also in part, I believe, to lack of appreciation of the gems that were growing there at the time.
Trees to be found in the park now are limited to date palms, Washingtonia palms, Conocarpus trees – all excellent specimens, it must be said and a pair of magnificent examples of Albizia lebbek, discussed in last month’s article – which are all that remain of the original planting arrangement.
Across the road, however, via the elevated pedestrian crossing, in Andalus Garden, there is a strong botanical flavour with date palms providing protection for a host of ornamental trees.
These include Tabebuia rosea (Rosy Trumpet Tree), Millingtonia hortensis (Indian Cork Tree or Tree Jasmine), Delonix regia (Royal Poinciana), already mentioned, Azadirachta indica (Neem Tree) and Cassia fistula (Indian Laburnum).
The planting principle reflected here is that found in a typical Bahraini date palm plantation, though instead of ornamental trees, fruit trees are the beneficiaries of its protective cover.
It is a principle found in no other Gulf country that I have visited and therefore unique to Bahrain.
The variety of tree shapes and foliage characteristics found in a Bahraini date palm plantation give it both a comforting and dynamic dimension.
I believe it is this that makes Andalus Park such a magnet for walkers who use it in the evenings, the dynamic element putting a spring in their step !
In addition, the combination of tree shapes and the protective arching fronds of the date palms and not forgetting the architectural features within the park, provide a visually pleasing scene.
This characteristic could be extended with great benefit to the wider urban scene, leading to the creation of urban oases.
With TSE becoming available and in the future condensate water, as well, there is no reason why urban oases and indeed oasis towns in Bahrain cannot become a reality.
It is thanks to the gardeners of Bahrain that we, the general public, can still enjoy a wide variety of ornamental flowering trees and shrubs – the public spaces as it were, borrowing from private gardens.
A striking example of this caught my eye the other day as I was driving along Old Palace Road – a tree, embracing a building, had clambering through it a wonderful specimen of Rangoon Creeper (Quisqualis indica), dripping with panicles of red and pink flowers.
It is a joy to behold during the day and a heavenly experience in the evening, when it gives off a captivating fragrance.
Gardens are bursting with colour and the hues seem brighter this month than the same time last year.
It could be something to do with the heavy rains that fell during the winter having leached salts from the soil, allowing plants some relief from their constant struggle with this element.
Also, the hot weather seems to have arrived earlier this year and I get the impression that ornamental trees and shrubs are making a great effort to display their glory, before succumbing to the extreme heat of summer.
With the onset of the hot weather, plants must not be allowed to wilt. Soil moisture should be checked regularly and water applied frequently to ensure it reaches the lower depths and to encourage roots to penetrate deeper into the soil.
Some gardeners prefer to allow the soil to dry out somewhat between watering, as continuously wet soil can lead to water-logging and the development of fungus diseases; also, too much water causes chlorosis.
Chlorosis (yellowing of foliage), is evident in a number of young Neem trees recently planted around Manama and is particularly noticeable in the car park next to Andalus Garden and in the garden itself, where Eucalyptus trees are exhibiting the same condition.
While too much irrigation could be the cause, I rather think the reason is calcium carbonate in the planting mixture dissolving and increasing the pH, to the extent that iron is “locked up” and unavailable to be taken up by the roots.
The answer is to make sure that particles of calcium carbonate are not allowed to pollute the planting mixture in the first place, by removing them from the “garden sand” using a fine sieve.
The Neem trees in question would benefit from iron chelate applied in liquid form to the roots and foliage; otherwise, during the cooler months, they could be lifted and replanted in a properly formulated planting mixture.
A number of lawns appear to be exhibiting nutrient deficiency symptoms, perhaps caused by too much irrigation water, resulting in nutrients being leached out of the soil, in which case the irrigation cycle can be adjusted and complemented with light applications of a high nitrogen fertiliser.
I say light applications, as large doses can lead to scorching of the sward (leaf blade).
General tasks in the garden this month include watering, as already discussed, and frequent light applications of fertiliser will stimulate newly established trees and shrubs into rapid growth.
The garden should be kept free of weeds and a constant watch maintained for pests, particularly in respect of citrus trees, on which aphids, mites and mealy bugs can be a problem.
These can be controlled with applications of Malathion. Old palm fronds can be sawn off and palms planted or transplanted.
Container – grown trees, shrubs and herbaceous plants may be planted, the best times being early morning and late afternoon.
It is important that soil is retained around the root ball and that after planting the plant is watered regularly.
Remove spent annuals and those that have become leggy and replace with portulaca, Madagascar periwinkle, globe amaranth, Gloriosa daisy or kochia.
I started this article intending to write about the exotic palms that greeted me at the Budaiya Agricultural Experimental Station and somehow found myself on another tack.
However, these interesting subjects will be discussed in the July article, as well as other plants I saw there and which readers may find worthy of including in their gardens.
In the meantime – happy gardening, and, as an anonymous poet said: “One is never closer to God than in a garden” and one, might add – in The Garden of the Gulf !