Q: I have a Zebra plant and a Peace Lily that have leaves that seem to be dying and turning brown from the tips of the leaves. Eventually the leave turns brown about half-way up the leaf. The whole leaf never dies, and does not fall off. Otherwise the plant seems to be healthy. It is not all the leaves, just some of them.

A: When the tips or edges of a plant turn brown I deduce immediately that water is not reaching that part of the plant.

Leaf diseases usually cause round spots but water problems show up on the tips and edges.

The browning could be caused by a lack of water in the soil, by too much water in the soil (leading to root rot) and by a draft on the leaves.

Put on your Sherlock Holmes hat and look for furnace vents near your plants. Pull them from their pots to determine the health of the roots. Make sure they do not sit in a saucer full of water after you water them.

One of the three conditions I mentioned above caused the brown leaves. It’s up to you to figure out which one.