Q. I am having problems with my Chinese oranges and Californian limes in Defence, Karachi; the Chinese oranges are in pots and the leaves have developed yellow coloured patches. The trees are all in fruit but not like they were three to four years ago.

The earth was changed eight or nine years ago and I feed them with organic fertiliser twice a year. The California limes are also in pots but the fruit is smaller than it was a few years ago. The tips of the leaves turn brown and then the entire leaf turns brown and falls off. Advise please. Also, when is the right time to prune both species of trees?

A. Oh dear! Your trees are suffering, very badly, from malnutrition. They are lacking in all kinds of essential minerals and nutrients and this is what is causing leaf discolouration, leaf fall and sub-standard sized fruit. This problem is fairly common with all kinds of plants, edible and otherwise, cultivated in pots as people tend to forget that, just like humans, plants need regular feeding in order to survive. Changing the soil eight or nine years ago is a sure sign of neglect as is only feeding them twice a year.

Taking care of soil and water, two essential elements for plant growth, will solve half your gardening problems

Changing soil in very large pots, as necessary for trees, can be problematic but topping up the soil without disturbing the roots is easy and should be done using top quality organic compost, at least every three months. This compost will be pulled down into the soil by the living organisms present there with worms being just one example. Feed the trees with an organic, seaweed fertiliser and do this every four to six weeks around the year to keep them healthy and productive.

Water just once a week in winter, twice a week during spring and autumn and three times a week during intense summer heat. There is really no need to prune these trees aside from removing any dead, diseased or very over crowded wood — this is best done when the trees are neither flowering nor fruiting — plus, remove unproductive suckers on a regular basis.

Q. I have tried growing ‘Nimbo’ plants — Lemons — in my Clifton, Karachi garden. I bought the plants from a nursery. They had some buds and I tried to take care but the plants died after a couple of months. I tried a second time with the same result. I would be grateful if you will kindly advise on the right season for growing these.

A. There is no wrong or right time to cultivate lemon trees if they are pot grown. Bare rooted trees, usually on sale during January and February, are different and should only be purchased and then carefully potted up during these two months. Please see the previous answer for further details.

Ripening tomatoes

Q. I planted a lemon tree in a big pot and last year it gave many fruits. Now though, as the weather changed and the air is salty — I live in DHA, Karachi — the tree is starting to die. Can you please tell me how to save it? I also need to know how best to water it and what to use if it gets any insect infestation.

A. Your tree is not affected by the season and not, unless it is fully exposed, by salty air. I suspect incorrect soil conditions combined with lack of nutrition, is the reason. Use top quality, well draining, soil with a high percentage of organic compost and please read above for more information.

Q. I live in Peshawar and want to grow vegetables in pots. I want to start off with tomatoes and need to know the amount of water and sunshine the plants require. Additionally, what are the names of some useful organic fertilisers and debris?

A. Tomatoes require lots and lots of sunshine and daily watering, evening watering is best, especially when temperatures begin to climb. Ensure that pots are well drained as water-logging will kill the plants. Soil should have a high organic content and weekly feeding with organic fertiliser, preferably in liquid form, will be beneficial once the plants begin to flower and set fruit. Organic fertilisers suitable for tomatoes include seaweed fertiliser and homemade liquid feed made by soaking organic manure in water, draining off the liquid and then diluting it with nine parts water to one part liquid fertiliser.

Juicy limes

I will include details of how to make such feed in an upcoming column along with information on organic debris to be used in this and as mulch.

Q. I reside at a height of 6,000 ft in Rawalakot, Azad Kashmir and have tried to grow many different kinds of vegetables but failed. Please guide me what to grow and from where I can get seed. I do travel to Islamabad and Rawalpindi sometimes. I am not a farmer. Growing things is my hobby and I want to have my own kitchen garden.

A. Height is not a problem. I have grown all manner of fruit and vegetables at the same altitude in Bhurban for many years. Please pay attention to soil improvement — organically — and to watering requirements. Planting suggestions are given here on the first Sunday of each month. Seeds are easily found in garden and agricultural outlets in both Rawalpindi and Islamabad.

Q. I am from Hyderabad and want to grow ginger, garlic and cabbages at home. What kind of factors do I need to take care of? I know nothing about gardening and would be grateful for any tips.

A. Ginger and garlic both need relatively long growing periods and rich soil conditions so please prepare the growing area well and apply lots or organic compost or well rotted, organic manure about a month before planting. For full information on cabbages please check recent back issues of this magazine as the subject was covered in detail. Good luck!

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, January 11th, 2015

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