Nitrogen is the #1 cause of leaf burn Documented at several web sites.

In 50 something years of gardening never heard of gypsum used to counter leaf tip burn

#1 use of gypsum is to loosen non-sodic clay soils

#1 way to deal with leaf tip burn is a low NPK fertilizer

There are many things that can contribute to (Leaf Burn( but floride and lack of Nitrogen are not among them. This article by (Doc( and Katy Abrahamson about covers this problem. Mostly it occurs because of unknown reasons.

Here is a link that might be useful: Doc and Katy Abrahamson on Leaf Burn

Sorry, but fluoride is among reasons for leaf burn.

As stated in the article by George (Doc) and Kay Abraham which was linked to (just above), "Easter lilies, dracaenas, spider plants and marantas actually have been proven susceptible to leaf scorch injury from too much fluoride in their soil."

Among the several sources of fluoride which affect those senstitve plants is perlite (AKA sponge rock), fluoridated water, and some fertilizers.

So, dormilona, what plants are affected?

Beyond that, probably most common reason for leaf burn in potted plants is insufficient water to the top of the plant.

That can occur from multiple reasons, among them these:
-- dry potting mix; and/or
-- excess water at the roots; and/or
-- erratic watering; and/or
-- recently transplanted; and/or
-- excessively low humididty.

Hi, Jean - The plant in question is a Zebra Plant (Aphelandra). I've had it for a couple of years, but the leaves always get brown, starting at tips, and then drop. It is all stalk now, with very few leaves (but I want to encourage the brave little new ones). It hasn't flowered since its first season with me.

To all, thanks so much for your responses. I love controversy, so I'm intrigued by the conflicting opinions. Unless someone raises serious objections, I think I'll try putting a tablespoonful of gypsum in the Aphelandra and watch what happens.

You live in SoCal. You have low humidity much of the time. Aphelandra is a tropical plant that does best with HIGH humidity.

Bottom line --- Gypsum won't help.

Jean in Portland, OR
who previously gardened in Long Beach, CA, for 30-some years.

The amount of fluoride necessary to cause leaf burn in plants would be almost poisonous to humans, but if that amount was in your water your teeth would be brown anyway. If you read what the Abrahamson's wrote that is what you will read.

So that's why my teeth are brown....

Jean, thanks for information about humidity. Instead of gypsum, I will try misting aphelandra every day. Thx again.

Mist it with distilled water, and consider a humidity tray. Put plant on gravel and put water in gravel just not up to plant bottom, so it can evaporate and provide localized humidity.

This is a 16 year old post!! It would be surprising if the plant in question is even still alive...... 😊

btw, if anyone is still interested, fluoride in tap water used to irrigate houseplants is very definitely one of the causes of leaf tip burn. The issue is well documented, especially with plants that may be sensitive to it : https://www.google.com/search?client=opera&q=fluoride+houseplant&sourceid=opera&ie=UTF-8&oe=UTF-8

Yes, you can use gypsum to help container plants with leaf burn. Gypsum helps to add calcium and sulfur to the soil, which can help to improve plant health. You can add gypsum to the soil either by mixing it in when you are planting, or by adding it to the water that you water your plants with.