Many houseplants struggle with tap water due to chlorine, fluoride, and dissolved minerals. Here are five particularly sensitive species and how to keep them thriving.
1. Calathea (Prayer Plant)
Calatheas are notoriously fussy about water quality. Tap water causes brown, crispy leaf edges and can lead to leaf curling. The fluoride and chlorine in municipal water damage their delicate foliage.
What to use instead: Distilled water, rainwater, or filtered water. If you must use tap water, let it sit uncovered for 24 hours to allow chlorine to evaporate, though this won’t remove fluoride.
2. Dracaena
These popular houseplants are extremely sensitive to fluoride, which causes brown tips and streaking on their long, elegant leaves. The damage is permanent once it occurs.
What to use instead: Rainwater or distilled water work best. Reverse osmosis filtered water is also excellent. The fluoride in tap water accumulates in the soil over time, making the problem progressively worse.
3. Spider Plant
Despite being considered low-maintenance, spider plants develop brown leaf tips when watered with fluoridated tap water. This is one of the most common complaints from spider plant owners.
What to use instead: Rainwater is ideal and free. Distilled water also works well. Some people successfully use aquarium water, which contains beneficial nutrients without the harsh chemicals.
4. Carnivorous Plants (Venus Flytraps, Pitcher Plants, Sundews)
These plants have evolved in nutrient-poor environments and are extremely sensitive to minerals in tap water. Tap water will kill them, sometimes within weeks.
What to use instead: Only distilled water, reverse osmosis water, or rainwater. This is non-negotiable for carnivorous plants. The total dissolved solids (TDS) should be under 50 ppm.
5. Maranta (Prayer Plant)
Close relatives of calatheas, marantas show similar sensitivity to tap water. They develop brown edges, yellowing, and overall poor growth when given fluoridated or hard water.
What to use instead: Distilled, filtered, or rainwater. Marantas also prefer slightly acidic water, so rainwater is particularly beneficial for them.
General Tips
- Collect rainwater in clean containers for a free, plant-friendly option
- Let tap water sit out overnight to reduce chlorine (though not fluoride or minerals)
- Consider a water filter if you have many sensitive plants
- Bottom watering can help reduce mineral buildup on leaves
- Flush the soil occasionally with appropriate water to prevent salt accumulation
Your sensitive plants will reward your attention to water quality with lush, unblemished foliage and vigorous growth.