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Which Indoor Plants Are Sensitive to Fluoride in Tap Water?


Some houseplants are sensitive to the fluoride that is added to municipal tap water for the purpose of preventing tooth decay in humans.

The symptom of fluoride toxicity in plants is leaf necrosis (yellowing, then browning, leading to dead, scorched areas on the leaf), which appears mainly at the tips of the leaves and along the margins (edges), spreading inwards. This is typically described as ‘tip burn’.

Fluoride is a cumulative poison in plant leaves, and may accumulate gradually over time. It strongly inhibits photosynthesis and other processes, and moves in the transpiration stream from roots or through stomata (leaf pores) and accumulates in leaf margins (edges).

Once the leaf tips or edges turn brown, the damage is irreversible. Either trim off the affected leaf tips or whole leaves after the damage appears.

Fluoride in drinking water can cause Lucky Bamboo plant (Dracaena sanderiana) leaf tips to firt yellow and then turn brown

Indoor plants that are more susceptible to fluoride toxicity are monocots, including those from the Agave (Agavaceae) family, such as dracaenas, cordylines and yuccas; and the Lily (Liliaceae) family, such as spider plant, and lilies. A more detailed list is provided below.

List of Fluoride Sensitive House Plants

Spider Plant (Chlorophytum comosum) showing brown leaf tips
Spider Plant (Chlorophytum comosum) leaves with visible tip burn

Other Factors That Can Cause Indoor Plant Leaf Tip Burn

The presence of leaf tip burn doesn’t always indicate a fluoride toxicity problem. It is important to note that other factors can also cause tip burn in indoor plants, and these include:

How to Prevent House Plant Fluoride Toxicity

There is no easy way to remove fluoride from tap water. Instead we can use the following options to reduce the problem of fluoride injury and toxicity in fluorine-sensitive indoor plants:

Generally, fluoride in the soil or growing medium is not available to plants to take up. Roots take up small amounts of soil fluoride by diffusion, which results in a low concentration in the plant leaves. Inorganic fluorides usually only remain in solution (as fluoride F- ions) that are available to plants under conditions of relatively low soil pH (acidic conditions) and low hardness (low calcium levels).

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