Using too much fertilizer can damage or even kill your lawn and garden plants. This article answers the question, “What is fertilizer burn?” and describes the fertilizer burn symptoms as well as how to prevent and treat it.
What is Fertilizer Burn?
Simply put, fertilizer burn is a condition that results in the burning or scorching of plant foliage. Fertilizer burn is the result of over fertilizing plants or applying fertilizer to wet foliage. Fertilizer contains salts, which draw moisture out of plants. When you apply excess fertilizer to plants, the result is yellow or brown discoloration and root damage. Fertilizer burn symptoms may appear within a day or two, or it may take a couple of weeks if you use a slow-release fertilizer. Symptoms include yellowing, browning and withering. In lawns, you may see white, yellow or brown streaks that follow the pattern in which you applied the fertilizer.
Preventing Fertilizer Burn
The good news is that fertilizer burn can be prevented. Here are some tips on preventing fertilizer burn on plants:
- Fertilize each plant according to its needs. You won't get better results when you use more fertilizer, and you run the risk of damaging or killing your plants.
- Slow-release fertilizer reduces the chances of fertilizer burn of plants by releasing the salts into the soil gradually rather than all at once.
- Fertilizing your plants with compost eliminates the risk of fertilizer burn. Most plants thrive when fed with a 1 to 2 inch (2.5 to 5 cm.) layer of compost once or twice a year.
- Plants are more susceptible to fertilizer burn during a drought because the fertilizer will become more concentrated in the soil. Wait until moisture conditions improve.
- Never fertilize wet lawns or allow fertilizer to come in contact with wet leaves.
- Water deeply and thoroughly after applying granular fertilizer to rinse the fertilizer off the plants and allow the salts to distribute themselves evenly in the soil.
How to Treat Fertilizer Injury
If you suspect you may have over fertilized your plants, treat the area as soon as possible. Treat spillage by scooping up as much of the fertilizer as possible. The only thing you can do for over fertilized soil is flush the soil with as much water as it will hold over the next few days. Don't allow the water to run off. Toxic runoff can contaminate nearby areas and may get into waterways where it causes substantial damage to the environment. Water slowly to allow the water to sink in rather than run off.