by Elizabeth Shaheen
Bahrain’s garden nurseries sell their trees container grown. This involves some awareness on the purchaser’s behalf. The trees available will be of variable stages of maturity, from seedling through to semi-mature trees. Although a semi-mature tree will create an immediate impact to your garden setting, a juvenile tree would be much cheaper and more likely to transplant well and establish itself more quickly.
The choice is yours. However, essential factors should take precedence.
Ensure that the tree has a firm straight trunk and a healthy, vigorous top-growth. Your selection should have a good symmetrical shape and a balanced spread of branches. Avoid purchasing a tree that has stem die-back and browning foliage. Look for signs of disease.
Ensure that the root-ball is devoid of pests, disease or damage and is well developed. Reject a pot-bound tree with a mass of crowded roots or one with thick roots poking through the drainage holes, for it may not establish well and the resulting root system will likely to be unstable, with poor anchorage and therefore susceptible to wind rock.
It is equally important that the compost should cling to the roots, when you ease the tree from its container.
If the compost falls away then reject the plant, for the root system is not well developed.
All too often do I see a container with whirling contorted, thick roots above its soil level. This is a sure sign that the plant has out-grown its container.
The container diameter should be at least one sixth of the tree’s height. Note also the type of growing medium.
A tree that is containerised in a soil-based compost will settle in the ground more readily than one that has been grown in another compost, such as a commercial potting compost or coco-peat, as it will have less of an adjustment to make to the garden soil.
Within your garden, you may have a range of microclimates. Therefore, it is fundamental before making your purchase that you consider the site and select a tree suitable to that site.
Bahrain’s air is salt-laden. Therefore, trees that detest such conditions will be vulnerable to windburn and browning leaves.
Good choices are Delonix regia, Plumeria rubra, Acacia auriculiformis, Cassia macrocarpa, Cocos nucifera, Albizia lebbeck, Barringtonia asiatica, Cordia sebestena, Hibiscus tiliaceus, Lagunaria patersonii, Brachychiton acerifolius, Peltophorum Caesalpiniaceae and, of cause, the date palm, Phoenix dactylifera. These are the tried and tested salt-tolerant trees suitable to Bahrain, as are many more.
The most favourable time to plant your container-grown tree would be from autumn to late spring, for this allows time for the roots to establish themselves before the onslaught of summer.
Fundamental to successful growth is the initial soil preparation of the planting site. Prepare the site prior to purchasing your tree, as this will allow the soil to settle. Make sure that the site you select has good drainage.
To check the drainage pour water into a hole that is 12-24 ins (30-60cm) deep. If the water remains for some hours, then this is an indication of poor drainage.
Your new tree will benefit from as little competition from neighbouring plants as possible, for it will need all the water and nutrients it can get.
Therefore, remove all plant growth from the immediate vicinity and double dig the soil, working the soil to two spits (one spit equals a spade-depth of soil) incorporating organic matter into the lower spit.
Prior to planting your tree, stand the container in a bucket of water just below the rim of the pot. Soak the root-ball for one to two hours, topping up the water as needed.
Then prepare the planting hole, between three or four times the diameter of the tree’s root-ball and one and a half times the depth of the root-ball.
Place a strong support in the hole and knock it in, just off-centre and on the side of the prevailing wind.
Carefully lay the tree on its side and gently tease out the side roots, taking great care not to disturb the root-ball.
Lower the tree into the hole, spread out the loosened roots and then back fill with the top soil mixed with organic matter. You may need to adjust the soil beneath the root-ball to ensure that the level of the garden earth line marries with the level of the root-ball.
Do not plant your tree’s root-ball below nor above the garden soil line, as the former denies the roots of oxygen and the latter causes the roots to dry out.
Firm the soil as you plant and finally tread around the tree to ensure the removal of air pockets.
Fork over lightly and build up a mount around the tree, just outside the circumference of the hole, to help channel the water to the roots and water in.
It would be prudent to add a mulch 2-3in (5-7cm) deep around the tree.
In the early stages, keep the plant well watered.
Your tree will give you many years of pleasure.
Elizabeth Shaheen – GDN – 26 Feb, ’06