Q. I planted an Arucaria in my garden in Multan eight years ago. It is now 11 or 12 feet tall. Its top three to four feet were badly burnt by the summer’s scorching heat but the lower part of the tree is still green and growing normally. I need to cut off the burnt-up top part but need to know if I should do this now or wait until it has shed its dried-up leaves? I love this tree and am very worried about it.

A. Stop worrying please! Do not cut the tree at all. The odds are that, in time, it should recover. In doing so it may shed all of its burnt ‘needles’ — this is the technical name of Arucaria and other pine tree ‘leaves’ — and then grow new ones in their place.

If, however, the tree is burnt again next summer, you may have to consider cutting the top off to reduce it to a size which you are easily able to protect in the following years. If you find it necessary then perform this cutting/trimming during January or February only. Cold weather will reduce the chances of an infection setting in.

Tips and suggestions on what to do when your plants are in trouble

Q. I teach science to eight-year olds at a school in Lahore and have been collecting caterpillars so that my students can study their life cycle first-hand. In my research I came across an article of yours which included a photograph of the same caterpillars I have collected. Please identify them and, if possible, suggest a website where I can obtain more information.

A. You are doing a wonderful thing. Teaching children about the natural world is extremely important as they are the guardians of tomorrow. The caterpillars photographed for that column were Pieris rapae — more commonly called ‘Cabbage White’. There is a well-known book, The Butterflies of Pakistan, authored by the late Tom J. Roberts, which contains all the information you need.

Q. I have a four-month-old papaya plant in my Karachi garden. It is a female plant about five-feet high. The problem is that it sets fruit but drops them when they are about an inch long. I think that the fruit drops because it is unfertilised in the absence of a male plant. I need your advice.

A. You’re right, your papaya needs a male companion before she will fruit successfully.

Q. I am a forester and work at a hilly place in Balochistan where the soil is barely fertile and shallow. I have tried growing trees there but the results have not been satisfactory. What would you suggest?

A. The forest tree most suited to the growing conditions you describe is Pinus sylvestris or Scots Pine as it is more often called. This species adapts to incredibly difficult and diverse conditions: it is not demanding as far as nutrients are concerned and young trees quickly develop an anchor system of strong roots to hold the trees in place.

I am not certain if the species is easily available in Pakistan but, if not, seeds should be easy to obtain. Robinia pseudoacacia is also worth a try although the wood is not commercially viable.

Q. Should I soak the roots of bare-rooted roses for at least 24 hours before planting?

A. Yes. Soaking bare-rooted roses — this applies equally to all other plants / shrubs / trees purchased bare rooted — is an excellent thing to do as it increases their survival rate tremendously. The correct preparation of planting holes, e.g. placing a mix of bone-meal, a few iron nails and an actual, totally clean, beef knuckle bone in the base of the planting hole is recommended. This combination will help the roses get off to a good start and will continue to feed them, slowly, for months to come.

Q. When can I sow the seeds of the following in Lahore: Spanish flag, lupins, Canterbury bells, moon flower vine, Echinacea, hollyhock, parsley, oregano, lemon basil and thyme? Can I grow the aforementioned herbs in pots? Additionally, can I sow seeds of beef tomato and habanero peppers now and grow them over the winter. I have leaf compost, manure and some good soil to grow them in. What should be the ratio of the mix and do I need to add fertiliser?

A. Sow Mina lobata as soon as it’s warmer and spring time. Soak the seeds for 24 hours. Do the same for moon flowers. Lupins and Canterbury bells should, ideally, have been sown last month but you can sow them right now along with Echinacea and hollyhocks.

Parsley, oregano and thyme can all be sown now but keep the lemon basil for spring. The herbs can all be grown in suitably-sized pots or containers. You can also sow the beef tomatoes now but the plants will need protection from winter chill. Habaneros, like all peppers, needs warmth and hot weather to thrive. Summers are ideal but make sure the Habaneros are protected from drying winds and kept watered.

They will not grow in the winter. A ratio of 25 per cent leaf compost, 25 per cent old, well-rotted, organic manure and 50 per cent top quality soil is perfect. No additional feeding will be required for annual (seasonal) species but perennial ones will benefit from organic fertiliser after six to nine months of growing time.

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, October 23rd, 2016