Plant Problem Diagnosis Key / Nutrient problems
Nutrient
Fertilizer burn (high salts)
High EC
Too much fertilizer salt in the root zone pulls water out of roots and burns leaf tips. It follows heavy feeding, dry media between feeds, and salty water.
Signs
- Leaf tips brown first, then margins, on many leaves at once.
- White crust on the media surface, pot rim or drip lines.
- Runoff or slurry EC well above the feed EC.
What favors it
Feeding above the crop's EC range, letting media dry out between feeds, high-salt water, and little runoff in containers.
Prevention
- Measure feed EC and runoff or slurry EC; keep runoff close to the feed.
- Water to about 15-20% runoff in containers so salts do not build up.
- Use lower rates on seedlings and in hot weather.
Often confused with
NutrientPotassium deficiency
Growing conditionsDrought stress (underwatering)
NutrientCalcium deficiency (and tipburn)
Sources
- Fertilizer or Pesticide Burn on Vegetable LeavesUniversity of Maryland Extension
- Fertilizer Toxicity or High Soluble Salts in Indoor PlantsUniversity of Maryland Extension
- Excess Fertilizer or Salt Damage on FlowersUniversity of Maryland Extension
- Auditing Overhead Irrigation Systems in Container Nurseries: Leaching FractionAlabama Cooperative Extension
Treatment by crop
Cultural, biological and chemical options in the order to use them, and notes written for each crop.
Identification is free. Treatment is on the Home and Pro plans.
Questions in the key that lead here
- Look the plant over, leaf undersides included. Are insects, mites, slugs, eggs, webbing or droppings on it?
No, only damage or discoloration - Where is the problem?
Leaves - What does the leaf damage look like?
Color change without distinct spots - Where did the color change start?
Leaf tips and edges, brown and crispy - When did the edges burn?
After feeding; white crust on the media or pot
Not a match? Start the key or describe what you see.
More from university Extension: search Extension pages on fertilizer burn, or find a plant diagnostic lab through your state's Extension.