Q. I recently started planting my kitchen garden in Karachi. I dug up a corner of the lawn next to a bottle-brush tree for a start. This area receives plenty of sunlight and is easy to water. However, it was quickly destroyed by weeds and by the climbers which spread from the boundary wall: only a mint plant survived. I did my best on this piece of garden and cannot dig a garden somewhere else. I certainly cannot cut the climbers as they hold up the wall and look so nice. What do you suggest?

A. The area is definitely fertile! Prune any straggly growth from the climbers, fasten them, securely against the wall, tying in strong shoots as you go. Once this is done, get on your hands and knees to tackle the weeds and when cleared and the garden area is visible once more, make sure that you keep it this way so that whatever you decide to plant, has plenty of light and space in which to grow. Simple!

Q. I am confused as seed sellers label Ajwain as oregano, Plectranthus amboinicus sometimes as Ajwain and sometimes as oregano! If Ajwain is not oregano, then what is it and is there a source for oregano oil in Karachi?

A. Ajwain is botanically called Trachyspermum ammi or Bishop’s weed in English: All parts of this herb are edible / medicinal. Plectranthus amboinicus — alternatively, and confusingly, known as ‘Spanish thyme’, ‘Indian borage’ or ‘Cuban oregano’ is also edible but has nothing to do with the herbs thyme, borage or oregano! Oregano is Origanum vulgare to give it its botanical name and, this very useful medicinal and culinary herb, belongs to the mint genus of plants. Hope this helps. I am not aware of any source for oregano oil in Karachi.

Zahrah Nasir gives handy tips on growing plants in pots and crates

Q. I have limited space in the courtyard of my house — just sufficient for a small lawn but not for growing vegetables. I have a spacious terrace on the first floor of my house though. Is it possible to grow vegetables in crates made of wood and filled with earth and, if so, how?

A. As long as the terrace gets sunlight for at least six hours a day — yes. Recycle fruit / vegetable crates from the bazaar. Simply line them with a triple or quadruple layer of newspaper so that soil / compost doesn’t fall out and off you go. Alternatively, use very strong cardboard boxes: these retain water longer than wooden ones but have much life. Fill with good quality soil / compost to within an inch of the top and sow seeds as usual. Be careful not to overcrowd seeds: such crates / boxes have space for very few seeds / plants as, remember, they need space to grow; the amount of space depends on the species. Opt for smallish varieties of things like cabbage which needs lots of space and for dwarf root vegetables; long rooted ones may run out of soil depth unless the crates / boxes are extra deep. You may like to spread a sheet of heavy plastic on the terrace before placing the boxes / crates there, this will prevent staining from run-off water / soil / compost residues.

Q. I would like to know how to treat termite infested soil in a garden bed please. A number of previously healthy, mature trees — such as ‘champa’ and ‘maltas, have already died. Just a few Malaysian palms and Ixora have survived. Plants which do well in pots wither away once transplanted to this bed. Seasonal flowers though, do well there. We live in Clifton.

A. Please refer to the Aug 16, 2015 issue of the magazine — available on-line — in which there is a full column on this subject.

Q. I have several citrus trees, in large pots, on my house roof in Karachi. They have all been fruiting for the last three years. This year though, an orange and a grapefruit did not bear any fruit. The leaves of these and of several Chinese oranges are now much smaller than normal and are yellow at the tapering ends. Organic manure was given to all the trees in spring. Can I leave iron nails in a container of water and give the rusty water to the trees instead of burying nails in the soil? A couple of the young trees have also developed bad cases of leaf curl and have not responded to garlic water spray or hellfire spray. How often should leaf curl afflicted trees be sprayed for the treatment to be successful?

A. The trees sound to be short of essential nutrients / minerals: the rusty water is a good idea and will be better if you add one tablespoon Epsom salts per bucket before applying, in moderation, once a month around the year. Leaf curl is a fungal infection: garlic and hellfire sprays are for insect problems only. Remove badly infected leaves and dispose of them sensibly and then, in early January, spray all of the citrus trees with an organic, copper based fungicide or an organic lime and sulphur mix. Repeat after two weeks and again the following year. Fungal spores remain active in the ground for a long time and, even if you think the infection has gone, keep in mind that prevention is better than cure.

Q. I am new to gardening and would like to know which plants can be grown in a pot without a drain. I tried with a tomato plant but it died.

A. All plants which grow in soil / compost, unless they are pond plants, money plants and similar, need drainage. Make a drainage hole in the pot and stand it in a saucer / tray if you are concerned about water spillage: Otherwise, fill it with water, put in money plant cuttings or, if it is very decorative, use it for cut flowers.

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

Published in Dawn, Sunday Magazine, November 8th, 2015

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