Why does my spider plant have brown tips on otherwise healthy leaves?

On a spider plant this shows as a neat, dry brown point at the end of a leaf, on leaf after leaf, sometimes with a thin yellow band where the brown meets the green. The rest of the leaf stays green and striped, and the plant otherwise grows well, throwing runners and keeping its colour.

The most likely cause is what is in the water. The entry says fluoride and chlorine in tap water, or a long dry spell. The Royal Horticultural Society says the fluoride in tap water can cause browning at the leaf tips, and the NC State plant toolbox says that chlorine and fluorides in tap water can cause leaf tip burn. The spider plant is one of the species the page on brown tips names as unusually sensitive, so it shows the damage when its neighbours do not.

To confirm it in a minute, look at the other plants in the room. If they are unmarked and the spider plant alone has tips like this, the water is likely. Then push a finger into the compost to 2 or 3 cm. If it is bone dry, a dry spell is the cause. Look at the surface of the compost and around the drainage hole for a pale crust, which means salts from feed and water are building up.

Two other causes are worth ruling out. The RHS lists very dry air and bright sunlight among the causes of brown tips, so look at whether the plant stands beside a radiator or in a midday sun beam. And a plant fed more strongly than the label, or at every watering, browns its tips, whereas the entry asks for half strength monthly in the growing season.

Brown tips never turn green again, so judge the recovery by the new leaves. Switch the water and the entry says the difference shows within a couple of months of new growth. The RHS says you can snip off the browned tips in the meantime.

What this plant wants

The fix

Water with rainwater or water left standing overnight, and keep the compost evenly moist rather than swinging from dry to soaked. Trim the brown to a point with scissors.

Read on

Brown tips on otherwise healthy leaves

The same sign on any plant, with the causes in the order they are likely.

Spider plant care

Light, water, feeding, repotting and the rest of the entry.

Check it in the diagnoser

Opens with the plant, the part and the sign already chosen.