Q. I live in Lahore where temperatures range between 40°C-50°C during summer. I have a potted bougainvillea which is not blooming. How often should I water it and should I continue to keep it in a location that gets intense heat for 6 hours each day?

A. Bougainvillea does not mind heat, in fact it loves it, so this is not a problem. Water, however, is the bougainvillea’s enemy and the plant often refuses to bloom when watered on a regular basis. If planted in the ground, these plants rarely, if ever, need watering once they are established. In a pot though, I suggest that you give water just once a week from April to October and once every two or three weeks during the rest of the year.

Q. We need your help with our papaya, chikoo, lemon, ponytail plant and many other plants too. We need to know why they are not growing when we have provided them with everything they need. Nothing in our garden grows properly. We live in DHA, Phase 5, Karachi.

A. Sorry to disagree, but if they had ‘everything they need’ they wouldn’t just be growing, they would be flourishing. That they are not, indicates that something is seriously missing and I suspect this to be soil nutrition. Healthy, well-fed soil, results in healthy plants as long as they are correctly watered. I strongly suggest that you upgrade the soil throughout your garden. This can be done, over a period of time, without removing your existing plants and trees. Not having any idea about the size of your garden, I am unable to specify the quantity of soil and other inputs necessary but, basically, you need to do the following.

Thoroughly clean and tidy up all of your garden beds and borders, removing all weeds, stones and other debris in the process. Purchase enough new sweet earth to spread on top of the existing soil to a depth of 4-6 inches (10cm-15cm), except around existing plants/ trees where it should be no more than 1-2 inches (2cm-5cm) deep. Over the following month, the new soil, assisted by regular watering and by the hard labour of industrious insects, will slowly settle in to place. Next, cover the settled soil with a 2-3 inch (5cm-8cm) layer of top quality, preferably organic, compost, again taking care to spread it thinner where it is close to existing plants/ trees. As long as your watering routine is suitable for whatever plant species you are growing, this thorough topping up of soil/ compost should begin to have a visible effect on plant health within 2-3 months. Maintain future soil nutrition by topping up beds and borders with about 2-3 inches (5cm-8cm) organic compost/ old, fully rotted, organic manure at least once, preferably twice, each year.

All your gardening queries answered here

Q. We have a chikoo tree that is more than two and a half years old, but it has yet to bear any fruit. How much longer do we have to wait?

A. Chikoo trees can take five to eight years to begin bearing fruit, so you may still have quite a wait on your hands.

Q. What are the best months for sowing corn in Karachi?

A. March and April are both ideal.

Q. I bought a raat-ki-raani plant in May and transferred it into a large pot soon afterwards. Two weeks after the transfer, it is not growing well at all and its leaves look dirty. I washed some leaves but, after drying, they look dirty again. Some of the leaves are curling longitudinally but on opening them there is nothing abnormal such as insects or fungus to be seen. The leaves are turning yellow from their tips and falling off. I water it every second day. To protect the plant from the scorching heat of Karachi, I have kept it in a place where it doesn’t receive direct sunlight after Zohar. Can you guide me as to what the problem is and how to solve it?

A. You are seriously overwatering your raat-ki-raani (cestrum nocturnum) plant. This overwatering is causing the leaves to curl and turn yellow, plus, the dirty looking leaves are infected with the fungal disease known as mildew. The mildew appears when humidity is extremely high and, aside from the Karachi climate in summer, is being caused by overwatering. Perhaps the drainage hole in the base of the pot is blocked and not allowing excess water to drain away. Check that the drainage hole is clear and reduce watering to just once a week when natural humidity is high (as in the monsoon season) and just twice a week during hot, dry weather. Hopefully your plant will recover, given time.

Q. My lemons are small in size and are not producing any juice. I used organic fertiliser but it didn’t work. What should I do next?

A. Fruit remains small and dry when not enough food and water are being given. Apply a citrus specific organic fertiliser, dosage according to the packet, once every three months. Water heavily twice a week when the tree begins to blossom and on until all fruit has been harvested. In periods when there is little or no fruit, watering can be reduced to once a week.

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, EOS, July 11th, 2021