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Growing Tomatoes: Do Your Tomato Plants Receive Too Much Fertilizer?

Tomatoes usually need fertilizer in order to produce a bumper crop, but you can have too much of a good thing. Excessive amounts of fertilizer can actually do more damage than good when it comes to your garden.

Nitrogen is an essential macronutrient that all plants need in order to grow and develop. Too much nitrogen, however, can cause scorched plants and poor growth.  Using fertilizers, especially synthetic ones, with high nitrogen content can be harmful to plants because fertilizers alter the soil by leaving soluble salts. High levels of salt pulls water away from the plant’s roots and tissues and dries it out, causing what is called fertilizer burn.

Signs of Excessive Fertilizer

  • Spindly, tall plants with little to no fruit
  • Yellowing or browning lower leaves 
  • Lack of growth at the top
  • A visible crust of white fertilizer on the surface of the soil
  • Browned and dried out looking leaves or roots
  • Scorched or burned look around the blossom end of fruit

Reversing Fertilizer Burn

Plants that have been mildly over-fertilized can usually be saved by using a few simple tricks. 

  • Flush the surrounding soil with water. Apply several inches of water to the soil several mornings in a row to wash away the excess salts.
  • Add mulch around the plant. The mulch will slowly draw the nitrogen out of the soil.
  • If there is a visible crust, carefully remove the top few inches of soil from around the plant and replace it with fresh soil.
  • Clip off leaves that are severely burned. 
  • Stop fertilizing for several weeks until the salts have been dissolved.
  • In extreme cases of burn, you can try to transplant the plant into different soil, but this does not always save it.

Avoid Over Fertilizing

The use of synthetic fertilizers is more likely to cause fertilizer burn because they are often heavy on nitrogen. If you do choose to use a synthetic, make sure that it is balanced and diluted according to manufacturer’s directions. Natural fertilizers are better for the soil because they promote the growth of healthy microbes and create a consistent source of nutrients for plants. They also tend to be more balanced in terms of macronutrients (nitrogen, phosphorus, and potassium) and micronutrients and trace materials. 

Tomato Secret

Dr. JimZ Tomato Secret is the best tomato fertilizer on the market today. With a superior blend of natural ingredients that feed the microbes in the soil and delivers direct nutrition to the plants, Tomato Secret will help you grow healthy, delicious tomatoes without the fear of over fertilizing. Simply apply one cup of Tomato Secret at planting, and then top-dress the soil after 6 weeks. For all of your fertilizer needs, head over to


A garden shovel for digging tomato plants.