Major, Secondary, And Micro-Nutrients: Signs Of Deficiency

Synthetic plant foods contain chemical nutrients to quickly add necessary nutrient to deficient soil and plants. Chemical fertilizers are an inexpensive way to help your plants produce bigger and better foliage, flowers and fruit. They contain a mixture of major, secondary, and micronutrients, so you can give your plants and soil exactly what they need. Understanding each nutrient and its signs of deficiency can help you choose which nutrients your gardens are lacking.

Major Nutrients

Your soil can become deficient in the three major nutrients: nitrogen, phosphorous, and potassium. 

Lawns and gardens deficient in nitrogen can show one or more of these signs:

  • Stunted growth
  • Yellowing of leaves
  • Fading lawn color

To add nitrogen to your soil, use a general fertilizer containing urea, ammonium nitrate, or IBDU.

Signs your plants are lacking in phosphorus may include all or some of the following:

  • Scorching along leaf edges
  • Burn between leaf veins
  • Yellowing of grass

To help plant suffering from a phosphorous deficiency, apply a phosphorous-rich fertilizer that contains diammonium phosphate. 

Potassium deficient plants exhibit the following symptoms:

  • Leaves change to a dull or dark green color
  • Bottom of leaves and leaf veins turn purplish-pink color

To effectively add potassium to your soil, choose a fertilizer that contains muriate, sulfate, or potash. 

Secondary Nutrients

Micro-nutrients that your soil needs, but may be deficient in include calcium, sulfur, and magnesium. 

Plants deficient in calcium can exhibit these symptoms:

  • New leaves grow smaller than normal
  • Foliage turns from green to reddish brown

When adding calcium to your garden, choose a fertilizer in the form of calcium nitrate or calcium carbonate.

Sulfur causes slow growth and other symptoms:

  • Wilted foliage
  • Yellowing of plant leaves

When applying sulfur choose a fertilizer that is readily available or use a high-sulfur fertilizer. 

Magnesium deficiency causes leaves to curl and foliage to turn yellow between the veins. Magnesium is an ingredient included in general fertilizers, but you can also buy it alone. 


Micro-nutrients include zinc, iron, and manganese. 

Zinc deficiency causes shriveling of plant leaves and new leaves are smaller than normal and deformed. Zinc oxide is usually included along with other nutrients in a general fertilizer. 

Iron deficiency cases new leaves to turn yellow and older leaves to yellow between leaf veins. You can add chelated iron to your garden or choose an iron-rich general fertilizer. 

Manganese deficient plants have yellowing of new leaves and older leaves slowly change from green to yellow. You can use manganese oxide alone or in fertilizer with a mix of micro-nutrients. 

Determining deficiencies in your soil can be difficult if you are not familiar with the various nutrients that plants needs. You can contact fertilizer companies, such as T And N Inc, or garden and equipment supply stores if you need help deciding what type of fertilizer your soil needs to produce healthy plants.