Q. I have a nine-year-old mango tree which fruited for the first time two years ago. But last year it didn’t and its leaves started drying and gradually dying. I didn’t know the cause so treated it with anti-termite. There wasn’t much change so I had its tertiary branches trimmed. Now it has new leaves. How can I prevent the previous problem from reoccurring so that the tree will fruit again? I reside in Rabwah near Chinot.

A. This sounds very much like an attack of a common bacterial disease generally referred to as ‘Fire blight’ or Erwinia amylovora to give it its scientific name. Although the Pakistani version may differ very slightly, the symptoms remain the same: Leaves turn brown and wither, they may or may not be shed by the tree, blossoms may form but fruit fails to set or, if it does, is distorted.

In severe cases, the bark may crack and blacken and the tree/branches look as they have been burnt. It can also get into the roots.

You may not have a green thumb, but Zahrah Nasir does! This week, she answers your gardening queries

Fire blight, a notifiable tree disease in many countries, is extremely difficult to control as the bacterial spores are air borne and thrive in warm, humid weather.

The spores enter the tree through the blossom or via damage to the bark. Trimming back all affected parts, down to ‘clean’ wood’ and spraying the tree, just as blossoms are beginning to form, with an organic copper solution, may help but — and especially if a neighbour’s trees are infected — it can be necessary to remove and destroy, by burning, entire trees. Sorry to be the bearer of bad news. Although, on a brighter note, trees, no matter how severely pruned, may eventually recover.

Q. We live in Lahore, Cantt and have a ‘Kungni’ palm which was healthy. Delicate new growth appeared but then we were shocked to find that, after some time, this new growth died despite being sprayed to kill pests that were attacking. The ‘adult’ leaves remain green but no new ones have appeared. Should the central flower and fruit be removed? How can we help it back to health?

A. Perhaps the spray you used, especially if it was very strong, was responsible for killing the new growth which, as you observed, was ‘delicate’. Please try to use organic rather than toxic chemical sprays if at all possible with, for example, a very strong brew of coffee grounds (not instant coffee), applied as a warm water spray being excellent for controlling / eradicating pests / scale insects on this particular palm species. Otherwise, it is natural for the flower / fruit to remain in place so just leave the palm alone, other than routine watering and it will, when it decides, send out more new growth.

Q. For the last two years I have planted gladioli bulbs. The resultant plants are healthy but did not flower. I bought the bulbs in Lahore in 2013 and planted some in pots and some in the garden but the result was the same. I took them out, saved them and replanted them the following year but yet again there were no flowers. I do not understand why as I grew gladioli successfully a few years back.

Almond blossom — Murree

A. It sounds as if you were sold immature bulbs which had not yet reached flowering size: they would send up lots of leaf but no blooms. For the bulbs to flower they need to be grown on, fed well and cared for so that they develop enough strength — and size — to flower in another year or two. Lifting them and putting them in storage does not allow them to grow on but keeps them at the immature stage. They must be left in the pots / ground. It is worth noting that immature bulbs cost less — or should cost less — than fully mature, flowering sized ones, but if flowers are what you want and as soon as possible, it is worth paying more for the largest bulbs you can find.

Q. I sowed almonds but even though they have not grown yet, I want to know how to care for them in summer. I live in Rawalpindi and some people say that almonds only grow in cold places. Last time I grew them, they reached one foot in height but then died.

A. Your enthusiasm is wonderful but, unfortunately, it is correct to say that almonds will not thrive in Rawalpindi: They really do prefer to be grown in much cooler areas — Murree being the nearest example to you. I suggest using your enthusiasm to propagate tree species, if nuts then look for ‘pecan’, suitable to your local climate.

Q. What plants do you suggest for a living wall?

A. Not an easy question to answer as much depends on where, exactly, the wall is to be: How much direct sunlight, what the wall is made of, watering arrangements, how much heat absorbent / reflecting material (concrete / glass) is in the vicinity, the season and much, much more.

It is, for example, pointless trying to grow a living wall of coloured lettuce in mid-summer, in a built up area of a city. Please provide full details so that I can give suitable guidance.

Q. We have a small orange tree which produces dwarf oranges. Is it in fact a tangerine tree?

A. Dwarf oranges are very different from tangerines: Tangerines have a loose fitting skin — as do their much larger relatives the ‘kinoo’.

Please continue sending your gardening queries to zahrahnasir@hotmail.com. Remember to include your location. The writer will not respond directly by email. Emails with attachments will not be opened.

Published in Dawn, Sunday Magazine, May 10th, 2015

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