Q. There is a huge mango tree in our Karachi garden. It is about 35 years old and gives 400-500 mangoes each year, but the problem is that it could give twice this amount as about half of the fruit falls off in the initial stages of growth. We feed the tree with manure purchased from a nursery. The tree is home to many birds so we don’t want to cut it down. Where are we going wrong?

A. The only wrong thing you are doing is failing to understand that your wonderful mango tree is doing incredibly well and that, irrespective of how good growing conditions are, a tree is only capable of bearing a certain number of fruit all the way through to maturity. The tree knows exactly how many fruit it can ripen so, quite sensibly, sheds any excess well before they drain its strength, thus allowing it to carry on and ripen the 400-500 mangoes it gifts to you each season. Please don’t criticise your tree, go out and thank it instead.

Q. We have a 25-ft tall mango tree grown from a ‘ghutli’ planted 10 years ago. It gets very little sunshine because there is a building in the way. The tree gets a lot of flowers but they all fall off. What can we do to make the flowers stay and turn into fruit? We reside in Clifton.

Answers to your gardening queries

A. There are a number of possible reasons for the flowers dropping: a) lack of sunshine; b) incorrect irrigation at flowering time; c) incorrect soil conditions; d) a lack of pollination/cross pollination; e) a combination of all of the aforementioned factors or f) the tree is infertile. Soil improvement may help, as may irrigation from when the tree is coming into flower until after they harvest — if fruit sets the next season.

If the tree is male, planting a female tree close by may eventually result in the tree fruiting and vice versa although if it is completely sterile nothing will ever make it bear fruit. Having made these points, it must also be stressed that plenty of sunshine is necessary for the health of a fruit tree and this, unfortunately, is something you cannot do anything lawful about!

Q. I love plants and herbs but live in a penthouse in Karachi and doubt if I can grow anything here.

A. It may be quite difficult to grow anything outside on your balconies/terrace as they will be exposed to the full blast of the wind, heat, salty air and the sun. However, there are many indoor plants you can grow as long as you shade them from direct sunlight streaming through your windows during the hottest part of the day. You will also need to select plants that will tolerate air conditioning so it may be best to start out by installing a few attractive succulents — easily found in local nurseries — and see how you get along with them before going for something more demanding.

Q. In your recent article on olive cultivation in Pakistan you didn’t include Sindh as an olive-growing area but I would like to try growing them in Mirpur Sakro. What do you think?

A. For the reasons given in the article you refer to, I advise against it.

Q. We shifted to a house in Rawalpindi which has a pomegranate tree. The problem is that while the tree bears many small fruits, the fruit gets infested with worms when it is ripening. Our neighbour had the same problem with a guava so he cut his tree down but we do not want to do that. How can the fruit be saved from worms?

A. Netting the tree as soon as fruit begins to form should prevent fruit flies from laying their eggs there; it is fruit fly larvae that ruin the fruits. If specialised netting is too expensive then use second-hand net curtains available at flea markets — such as Lunda Bazaar in Karachi — instead.

Q. Why do you recommend that we give priority to indigenous species of trees/plants over imported ones? Most indigenous ones are boring and not colourful but imported ones are absolutely gorgeous.

A. The facts speak for themselves. Indigenous species are climate/soil tolerant, have high resistance to indigenous pests and diseases and are a food source for indigenous birds, bees, butterflies and so on. Indigenous plants also tend to have very low water needs. Imported species are often problematic, need lots water (now increasingly scarce) and other inputs if they are to survive. Being ‘foreign’, they do not necessarily act as food sources for indigenous creatures of any kind.

Q. Where can I get red currant and cranberry bushes? I cannot find any retailers selling it, including on the internet.

A. These fruits are only suitable for growing in very limited, northern areas of the country and, as such, are not generally available. It is against the newspaper policy for me to name specific suppliers in my column but please search more extensively on the internet as I have seen sellers there.

Q. Is it mandatory to use new pots every time we sow seeds?

A. No. Reusing old ones is preferable to buying new but they really should be scrubbed out and sterilised first: otherwise plant diseases may be unwittingly transmitted.

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

Published in Dawn, EOS, June 25th, 2017