Q: I have a potted cacti display on a windowsill in my home office. A couple of the plants have recently developed unsightly, brown markings. What's caused this, and can I get rid of it?
A: For the most part, cacti are a dream indoor plant due to their undemanding, drought-tolerant nature. The brown markings may, however, be an indicator that something isn't quite right – from watering habits to too much sun. On the other hand, they can also be a natural sign of age, known as corking.
The first step is to identify the problem – and that's where these tips can help.
