Organic fertilizers can burn foliage just as easily as chemical fertilizers can.

• A. True
• B. False
• C. Sometimes
• D. Not sure

Answer: (B)

Fertilizer burn comes from high salt concentration around the roots pulling water out of plant cells and causing tissue damage. Chemical fertilizers often deliver nutrients in highly soluble forms, so if they’re over-applied or not watered in, the root zone can quickly become saline and scorch foliage. Organic fertilizers, on the other hand, release nutrients more slowly as microbes break them down, so the soluble salt load in the root zone stays lower and the risk of rapid osmotic stress is reduced. That’s why they’re generally safer for foliage when used at proper rates and watered in. There can still be burn with organic materials if you apply too much at once or use fresh manure or other high-moisture content materials without adequate irrigation, but the overall risk is typically much lower compared to chemical fertilizers.