What happens when you get a runny nose and a cough, do you go to the doctor? Did you know that just like you, plants can get sick too? We know that germs make us sick, but what makes a plant sick?

Not only do plant need water to be healthy, they also need nutrients! Nutrients are a plants version of food or energy. They play a key role in the growth and survival of plants all over the world!

So how do you know if your plant is sick?

When a plant lacks the right nutrients, it starts to develop symptoms just like your runny nose and cough! There are 16 nutrients that affect plant health. Most of these can be found in soil and each nutrient affects plants in different ways.

3 of the most important nutrients in garden soil are Nitrogen, Phosphorus, and Potassium or NPK! Lets identify their symptoms!

Nitrogen (N)

Nitrogen is an important nutrient for leaf growth in plants. A Nitrogen deficiency is very common in plants.


Signs you might see if a plant needs Nitrogen:

  • Reduced growth (left picture)
  • Yellowing on leaves (old leaves first) (right picture)

Phosphorus (P)

Phosphorus is important for root growth, especially in young plants and seedlings.


Signs you might see if a plant needs Phosphorus:

  • Thin stems
  • Loss of lower leaves
  • Reduced flowering
  • Turning purple (right picture)

Potassium (K)

Potassium is important for flower and fruit growth, and protections against frost, drought and disease.


Signs you might see if a plant needs Potassium:

  • Reduced growth
  • Burnt/brown leaf edges (left picture)
  • Dead spots on leaves (right picture)
  • Easy wilting
ACTIVITY: Plants can sometime show you that they need nutrients. Look at each picture below and make a guess what the plant needs. When you think you know, click on the picture and read the caption at the bottom to find out.