Q. I have a 1,200 sq-yard plot that I want to grow vegetables in, but there is a major problem with weeds. Due to a permanently leaking, six-feet-in-diameter water pipeline that passes close by, there is excess water which — after digging a deep trench — is channelled into a well so that it doesn’t go to waste. The land now is not waterlogged. The problem is that, while the land was getting so much water, weeds — with roots going down four to five feet — got well-established. I had hired four labourers to dig out every single weed complete with roots. After that, a tractor dug over the plot again, followed by labourers picking up every single piece of weed root. This, however, has not stopped the weeds from sprouting again. How can I get rid of them so that I can grow vegetables?

A. The weeds have obviously had time to get well-established and will have scattered a massive amount of seed into the soil: this seed has the potential to keep on germinating for years. Digging the plot over will have further disbursed the seed. The most effective solution I can recommend is to hire a professional, full-kitted out person to blast every square inch of the plot with a horticultural flamethrower to kill as many of the remaining weeds seeds as possible. I dislike this method as it completely sterilises the soil and eradicates important macro-organisms from the soil, along with essential insects such as worms and beetles, but it is far preferable to using toxic chemicals.

After this sterilising is done, you will need to add copious amounts of old, well-rotted, organic manure and organic compost — and to repeat this process after each crop has been harvested. Over time, this will rebalance the soil and make it healthy again. There will, naturally, still be some weeds popping up in the soil as weed seeds do come in manure and are dropped by birds, as well as carried by wind, but regular hand-weeding should take care of these. These weeds, as long as they are removed when young and well before they reach the seeding stage, can be added to one of the compost heaps/bins you need to establish for maintaining long-term soil health.

All your gardening queries are answered here

Q. I would like to know if vanilla beans will grow in Karachi or not. If so, where can I get the plants?

A. I believe that vanilla orchids have been grown in Karachi but only in greenhouse conditions where humidity levels can be permanently controlled. Contact the local orchid society for advice.

Q. I am new to gardening and am trying to learn the basics. I would be grateful if you can tell me what ‘sweet earth’ is and its local name. Also, what ‘ordinary garden soil’ is and what is it called locally?

A. Kali mitti (sweet earth) is top quality soil and is often blackish in colour and mitti (regular soil), is much denser, tends to contain a high percentage of ‘heavy’ red clay and is best mixed with river sand/loam and manure before use.

Q. What are the components of ‘well-drained soil’ and what percentage of each of these components should I use to make well-draining soil?

A. Soil that drains well usually contains approximately 25 percent river sand which helps stop soil compacting, thus allowing water to drain through. But this water must still have a place to drain into: it can drain through a sub-soil base of a similar mix, of small to medium-sized stones or via drainage ditches/pipes.

Q. We reside in Lahore and have a 12- or 13-year-old mango tree. It used to bear much fruit but hasn’t fruited at all for the last three years. We had to remove another smaller mango tree because we had too many trees in the garden: they were overcrowded and sunlight was lacking. Apart from overcrowding the team which used to come and spray against dengue mosquitoes didn’t mix the spray correctly and it burnt the leaves off the mango tree that has since been removed. The remaining tree — the one which has stopped fruiting — survived and grew new leaves. I don’t know much about gardening so would appreciate your help.

A. Your mango tree may still be suffering from shock caused by having its leaves burnt. Feed it and water it well and keep your fingers crossed that it does begin to fruit again in time.

Q. I intend to cultivate olive trees in Skardu, Gilgit-Baltistan. Winter temperatures fall to minus 10 degrees Celsius and sometimes less. Summer temperatures are favourable. Please guide me.

A. Sorry. Winter temperatures in Skardu are too low for olive trees to survive.

Q. I want to grow strawberries in Chitral. There is snow fall in December, January and February and summer is normally hot in July and August. Is this suitable for strawberries?

A. Strawberries do well in your locality.

Q. I read your article on Lavandula Augustifolia and am wondering if this plant is available in local nurseries now. 

A. As you failed to mention your locality, I have no idea what plants your local nurseries have in stock. If you are in the Islamabad area you may strike it lucky.

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, April 14th, 2019