Dr Christopher Teh, soil biologist and senior lecturer at Universiti Putra Malaysia, answers gardening questions in Star2’s gardening column, Ready, Set, Grow! To send him your questions, fill in the form at the website questions.eatsshootsandroots.com.

My curry leaves develop dried brown patches when the leaves grow bigger. What can I do to have all green leaves? – Soo

The leaves in the photo seem to be eaten, leaving a skeleton-like or window pane appearance on the leaf surface.

Try examining the leaves more closely and check the surrounding area. Do you see any beetles or larvae? If you see strange, alien-like beetles, they could be the tortoise beetle. Pluck them off the leaves and try to remove them entirely from the surrounding area.

You could also try spraying with neem oil and water mixture for pest control.

Questions for the Plant Doctor about plants developing white patches

If you see white patches like these, look out for a mealy bug infestation. Photo: Eats, Shoots & Roots

I noticed that my plants have whitish specks on the leaves. What are they and what can I do to get rid of them? Thanks. – Felicia

It looks like mealy bugs. Take a closer look at the white specks, and you should see powdery white and soft body insects, about 2mm long.

If you have only a few infected plants, the best method is to simply wipe them off the leaves. Keep doing this until they are gone.

Alternatively, you can spray a neem oil mixture as pest control.

Star2‘s gardening column, Ready, Set, Grow!, which appears on the fourth Wednesday of every month in print, is brought to you by social enterprise Eats, Shoots & Roots.