University of Maryland Extension

Fertilizer Toxicity or High Soluble Salts

fertilizer damage houseplant

High soluble salt levels are caused by the excessive use of fertilizers, frequent applications of fertilizer, and the incorrect use of fertilizer concentrates.


  • The typical symptoms are browning or dieback of the leaf tips and margins. But can include reduced growth, lower leaf drop, dead root tips, and wilting. 
  • Sometimes yellowing or stunting may occur. The root systems will also show dieback and decay.
  • Fertilizer salts may also accumulate on the surface of the potting media as a white crust, especially if bottom watered, and cause stem collapse at the soil line.
  • Salt deposits may be visible on the outsides of pots.


  • Use the proper fertilizer analysis at the correct rate and frequency.
  • Large pots with growing media that have excessive salts can be flushed or leached by irrigating with clear water.
  • Allow the water to run out the bottom of the pot and repeat the several irrigations with a volume at least that of the pot size.
  • Smaller pots with media high in salts should have the growing media replaced.
Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2020. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.