Gardening: Readers' problems solved | Brian Kidd (Nov 29)

Q: I would like to do my bit for improving air quality and would love to plant a tree – one which will not cover the garden and one which will not need constant pruning. VM, Fratton.

A: It would be great if everyone planted a tree. This is possible even if you live in a flat. One can be easily grown in a big pot and the tree I would recommend is Prunus amanagowa. It’s upright, its branches do not spread and it has pink flowers in spring. Great for producing oxygen.

Q: I enclose a live specimen of what looks like a miniature dragon. Is it friend or foe? BM, Cowplain.

A: Thank you for leaving this in our porch. It is the larvae of a ladybird. I have put it in the warm part of our greenhouse so will survive the winter. This baby was born during the warm spell we had in late August. It’s rather unusual and, bless its heart, it will make it to adulthood.

Q: My dad has a huge hibiscus in his conservatory. It has reached the glass ceiling and it is difficult to walk around. I must prune it while he is on holiday. How hard can I prune it? HD, Southsea.

A: Cut off between half to three-quarters of every side branch and take 24in off the top. This may seem a bit drastic but next summer there will be lots of blooms. If your dad complains, show him this and he can blame me!

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