Diagnosing Plant Problems

A Guest Post

As plant experts, we know an all too familiar moment. Our friend calls us up, rambling on about brown or wilting leaves, asking us what's wrong with my plant?

To help you answer this question, we're going to cover some common plant problems, including diseases and issues with the environment. And we'll explain the steps you can take to diagnose plant problems, so you can get your plants back on a healthy track.

Guest Post - Diagnosing Plant Problems

How to Diagnose Common Plant Problems

With thousands of plants in the world and thousands of possible issues, it can be difficult to determine what's wrong with your plant. But, by following these steps, you'll be on your way to figuring it out.

1. Look at the Symptoms

No matter if your plant is in growing outside in your garden or in a pot on your windowsill, the first step is to take a good look at what's wrong with it.

Along with taking note of what problems exist, observe where they are occurring and to what extent. For example, if your plant's leaves are yellow, are newer or older leaves yellow? Or are all the leaves yellow-green?

Also, note when these problems started occurring and how long they've been present.

2. Check the Environment

Noting the area your plant is living in, along with any recent changes, can help you figure out what's wrong with your plant. Along with observing the current environment, think about any recent changes.

Take a look at the following factors:

  • Light
  • Temperature
  • Humidity
  • Soil type
  • Water

3. Narrow it Down

Once you've looked at your plant's issue and the environment it's living in, it's time to figure out what's responsible for your plant's problems.

To start out, try to narrow it down to one of four categories of plant problems.

  1. Environment problems
  2. Nutrient problems
  3. Pests
  4. Diseases

We're going to break these four categories down to help you figure out which one your plant is dealing with.

Environmental Problems

A plant's environment can dramatically impact the plant's health, both in a short period and over a long amount of time. To make sure your plant is in the proper environment, take a look at the following environmental factors.

Water: All plants need water to survive, but there is a thing as too much and too little water. If your plant is receiving too much water, it may show soft roots, discolored leaves, or mushy stems. Plants that aren't getting enough water may show crispy leaf tips and wilt.

Light: Different types of plants require different types and amounts of light. If your plant has areas that looked faded or scorched, it may be receiving too much intense light. Alternatively, plants that don't receive enough light may have small leaves, no new growth, or a general lack of vigor.

Temperature: Both prolonged periods of inadequate temperatures as well as short bursts of super high or low temperatures can harm and even kill plants.

Soil Type: The wrong soil type can lead to issues with water-holding and aeration. If your plant looks stunted, check the soil type to make sure it's allowing your plant to obtain the air and water it needs.

If you notice your plant has developed problems after you moved it, there's a good chance the new environment is causing the problems.

Nutrient Problems

All plants require 18 different nutrients, including 15 mineral nutrients. If plants aren't getting all the nutrients they need — or too much of a nutrient — they will exhibit specific symptoms.

To determine what nutrients your plant is lacking, you'll need to compare your plant's problems with symptoms of various nutrient deficiencies. However, you can easily narrow down what nutrient is missing by looking at where the problems occur.

If your plant has symptoms in new leaves, it is lacking an immobile nutrient that cannot move to new growth. These include boron (B), calcium (Ca), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), sulfur (S), and zinc (Zn).

If the symptoms appear in older leaves, your plant is lacking a mobile element like chlorine (Cl), magnesium (Mg), molybdenum (Mo), nickel (Ni),  nitrogen (N), phosphorus (P), and potassium (K).

Garden and House Plant Diseases

Just like humans, plants are susceptible to a variety of diseases caused by bacteria, fungi, and viruses. While there are thousands of possible plant diseases, some are more common than others. And many diseases can be treated in similar ways.

It's important to note that not all diseases affect all plant species. Many diseases require specific host plants, so you can use this information to help determine what's wrong with your plant.

If you notice any of the following symptoms on your plant, it may be suffering from a disease.

  • Rapid wilting
  • Discolored spots on the leaves
  • Powdery substance on the plant
  • Seedlings falling over at the base
  • Stunted plant
  • Yellowing leaves

If you do think your plant is infected with a disease, here are some common plant diseases to investigate.

  • Powdery mildew
  • Damping-off
  • Anthracnose
  • Botrytis
  • Various rusts
  • Septoria leaf spot
  • Bacterial wilt

Insect Pests

If you notice insects on your plant, they may be the cause of your plant's problems. But, there are also beneficial insects, so don't assume every insect is bad! Also, just because you don't see insects, doesn't mean they aren't to blame — many insect pests are small and hard to spot.

Insects can harm your plant in many different ways, including by sucking plant sap, chewing through leaves, and spreading disease. After you've noted your plant's symptoms as well as what any visible insects look like, try to determine what the insects are.

Here are some of the most common plant insect pests.

  • Aphids
  • Spider mites
  • Thrips
  • Mealybugs
  • Fungus gnats
  • Stink bugs
  • Whiteflies
  • Japanese beetles
  • Codling moths

If you think your plant is infested with insects, act fast! Many pests breed quickly, leading to populations that can quickly get out of control.

Wrapping Up

Now that you know more about what can cause plant issues and how to properly diagnose these issues, you're ready to figure out what's wrong with your plant and start treatment. With some care and patience, your plant will be looking healthy before you know it!


Julie Jenkins is a Gardening Expert specializing in organic vegetable gardens and soil health and sharing garden inspiration & helpful tips to grow your garden.