The Effects of Salt

• The salts comprising granular and liquid fertilizers are by themselves potentially harmful to plants unless diluted or released at a rate in the soil that does not harm plant roots or leaves. Concentrated salts cause desiccation of living plant cells, often causing a rupture of cell walls. You can better understand the harmful potential of fertilizer salts much like how saltwater feels against your skin compared to freshwater. Saltwater dries the skin and is painful when brought in contact with open skin wounds or your eyes.
  
  

Follow Label Directions

• To avoid fertilizer burn on plants, it's vital to follow the prescribed dosages and application procedures on fertilizer product labels. Fast-acting fertilizers contain salts that readily dissolve in water, whereas insoluble fertilizers, or slow-release fertilizers, require weathering or decomposition by soil microbes to release the salts for plants to use. Overapplying fertilizers, especially liquid or water-soluble types, increases the amount of salts touching plant leaves or roots. If the salt concentration is too strong for any particular plant species, fertilizer burn occurs.
  
  

Symptoms

• If you place fertilizers in specific areas of a garden bed or across a lawn, fertilizer burn manifests by wilting or yellowing of plants that came in contact with the improper fertilization. Only plants with leaves or roots in contact with the excessive fertilizer salts show symptoms. The wilting or yellowing affects the entire plant. This is in stark contrast to other plant ailments, which tend to inflict small, localized parts of a plant.
  
  

Preventing Fertilizer Burn

• Always apply the correct amount of fertilizer product to plants. Do not assume by doubling a dosage that you are hastening a plant's ability to grow better in a shorter time frame. Apply fertilizers to moist soil, or, if the fertilizer label advises, immediately water the garden area after application to wash the fertilizer off the plant tissues and onto the soil. Never apply fertilizers when a plant is stressed from disease or drought, as it may be more sensitive to the drying effects of fertilizer salts. Also do not apply fertilizers onto wet leaves. Particles of fertilizer salts may dissolve on wet leaves and instantly act against the healthy plant tissues they come in contact with.