What is Fertilizer Burn?

Mary McMahon
Mary McMahon

Fertilizer burn is a condition that emerges in plants that have been over fertilized. The excess fertilizer in the soil acts to actively pull water out of the plant, causing it to dryout and interfering with plant growth. The burn is visible as an area of browning, yellowing, and withering. If it is allowed to persist, the plant can actually die, especially if it is at a vulnerable stage of development.

A blue synthetic plant fertilizer.
A blue synthetic plant fertilizer.

The mechanism behind fertilizer burn is fairly simple. When plants are fertilized normally, they absorb salts and minerals from the fertilizer, maintaining a high osmotic pressure in addition to providing nutrients. Since water flows from areas of low to high pressure, the high osmotic pressure in the plant helps pull water up into it so that it can meet its water needs.

Organic fertilizer pellets.
Organic fertilizer pellets.

When too much fertilizer is applied, it creates a high osmotic pressure in the soil solution that surrounds the roots of the plant. This interferes with the ability of the plant to absorb water and can sometimes pull water out of the plant. Roots and leaves alike can be damaged, causing a plant to become unhealthy. Fertilizer burn can also happen when fertilizer levels are relatively normal, but the plant is not getting enough water.

Sometimes, the burn appears almost immediately after excessive fertilization although in other instances, it may take several weeks for signs of damage to appear. This is especially common with organic and time release fertilizer products, in which time is required for salts to start building up to a dangerous level. Treatment involves removing the excess fertilizer, if possible, and flushing the soil with water to remove the buildup of salts.

People can avoid fertilizer burn by making sure that the needs of their plants are met without exceeding them. Any fertilizer product is capable of causing burn, no matter what the label says, and it should be applied in moderation and in accordance with a strict schedule to avoid using too much. In addition to being damaging to the plants, over fertilization can also be harmful for the environment, as it generates runoff that can pollute waterways. Nutrient pollution leads to a proliferation of algae and other organisms in the water, which can interfere with water quality and hurt fish populations; in waterways that drain to the ocean, it can cause problems with sea life as well.

Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a wiseGEEK researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

You might also Like

Readers Also Love

Discussion Comments


If I accidentally 'burned' perennials and we cut the dead parts off, can we do anything to help them re-grow next year?


I have a couple of shrubs that I fertilize and they are turning brown. Can they still be saved and how?


I have a fig tree in a pot that I over fertilized with 10-10-10 and it's turning brown. Can it still be saved if I take it out of the dirt and place it in a bucket of water for a few days then replant it in fresh new dirt?


@ceilingcat - If your plants don't make it this time, I would strongly urge you to just follow the directions on the phosphate fertilizer next time. I know it can be tempting to overdo the fertilizer but as you know it can hurt your plants in the long run.


Until recently I had no idea there was a such thing as too much fertilizer for a plant! I just started gardening and I was giving my plants tons of what I thought was the best fertilizer. After a few weeks my plants were looking horrible and I think fertilizer burn is the problem.

I'm hoping to use some of the tips in this article to save my plants but if it doesn't work at least I'll know for my next try!


My uncle maintains the green at a golf course, and because he has to keep the grass in excellent shape there, he must push turf feeding to its limit at times. He has to watch carefully for any signs of wilting, and if he sees any, he has to test to see if the grass is excreting any nitrogen. If it is, then a whole crew has to leach the fertilizer from the soil by washing it with large amounts of water.


I am so glad I read this article! We have been experiencing a dry spell here in the South, and my flowers, which normally would be in full bloom by now, have been holding back. I have been fertilizing them to help them along, but now I see that I may actually be damaging them by unknowingly draining them of water.

Post your comments
Forgot password?