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Why Are My Mums Turning Brown? (4 Common Causes)

Why Are My Mums Turning Brown? (4 Common Causes)

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Chrysanthemums are generally low-maintenance plants that don’t usually have problems, but there can be exceptions to this. There are some problems that can cause your mums to turn brown, so let’s go through and see if you can get your plant back to full health!

There are several reasons why your mums may start turning brown; some of these include improper watering practices, problems occurring with the mum’s soil, disease can begin turning your mums brown, as well as a pest infestation. These should be dealt with fast as they can kill your plant.

Mums or Chrysanthemums are stunning plants, but they can have a few problems. The list below can help you troubleshoot what could be causing your mums to turn brown and how to fix the problem!

Why Would Mums Start Turning Brown?

It is discouraging when your beloved plant that you put so much effort into begins to seem quite worse for wear and begins to turn brown.

The issue with this is that many causes could make your mums turn brown, so it can be extremely challenging to figure out what is going on with your plant and how to treat it if you can treat the problem at all.

Here are the reasons your mums may be turning brown:

  • Improper watering
  • Problems with the soil
  • Diseases can start turning mums brown
  • An infestation of pests

A lot of these problems that can turn your mums brown can also lead to the death of your mums if they are not treated as soon as you see them. So, let’s go through all these causes more in-depth and see how you can treat them and if you can possibly avoid some of these problems in the future.

1 – Improper Watering Practices

Watering Chrysanthemums

If you do not water your mums correctly, this will negatively affect your plant. Mums have very shallow root systems, which means they need to be watered regularly at the topsoil is always the first part of the soil to dry out.

If this happens, then your mum’s roots cannot reach the moist soil lover down, which could dehydrate your plant, cause its leaves to turn brown.

Overwatering your mums can also cause the leaves to turn brown. If the soil is too saturated with water, the plant cannot absorb the right amount of nutrients it needs to survive as they are all extremely diluted. This can also cause root rot to develop.


You need to ensure you water your mums correctly. The amount of water required and the regularity of the waterings will be determined by the climate you keep your mums in. If you reside in an environment with little rainfall and hot summers, you will need to water your mums more regularly.

If you receive a lot of rain and the temperatures do not go very high, then you may not have to water your mums at all.

However, the rule with mums is the soil needs to stay moist, so if the soil begins to dry out, you need to water them.

2 – Problems with the Soil

Mums need to be kept in nutrient-rich soil for them to thrive. Mums require a good amount of nitrogen and potassium in their soil, and if these two nutrients are low, your mums will begin to turn brown.

Mums also require their soil to have good drainage and water retaining abilities. If the soil holds too much water, this can lead to problems developing like root rot, or if the soil is too well-draining, this can cause your plant to become dehydrated; both will turn your mums brown.


If you think that your mum’s soil is not nutrient-rich enough and is the cause of the browning, you can add some fertilizer to your plant’s soil. Ensure the fertilizer is at the ratio of 6-2-4 or 4-2-3, as these work best for mums.

If you think that soil drainage is the issue that is causing your mums to turn brown, then you can do one of two things. If it’s too well-draining, you can place some mulch on top of the soil, and if it’s not draining enough, you can repot your plant and mix some perlite into the soil.

3 – Diseases Can Start Turning Mums Brown

Pink Chrysanthemum After Heavy Rain

If your mum’s soil is too saturated with water or the plant stays wet for long periods due to rain, mums can develop certain fungal diseases that can cause the plant to turn brown. The most common types of fungal disease that you might face with your mums are leaf spot and brown rust.

There is also a disease called wilt disease that mums are susceptible to. This disease attacks the vascular systems of your plants, which causes the leaves to turn brown.


If fungal disease is attacking your mums, then you can go and buy an anti-fungal spray from your local garden store. A general fungal spray will easily kill both of these fungal diseases, so there is no need to purchase specific anti-fungal sprays for each disease.

Wilt disease lives in the soil of your mums and enters the plants through the roots. This disease is the cause of plants suddenly wilting and dying for what seems like no reason.

This disease is difficult to treat, but you can try a few methods to save your plant. You can feed your plant a growth enhancer to strengthen your mum’s immune system, and then place some warm castings on the surface of their soil, mixing it into the soil as best you can.

4 – An Infestation of Pests

There are a few pests that mums are susceptible to that can cause the mums leaves to turn brown. The pests you need to watch for are aphids and mealybugs that will suck the sap out of your plants, dehydrating them, which will make them turn brown.

There are also thrips that are a type of mite that can also affect your mums by attacking the flowers and buds of your plant. Thrips will bite the plant’s cells and eat the cell’s contents, which causes the surrounding tissue to die, turning parts of the plant brown.


To treat a pest infestation on your plant, buy an insecticidal soap and wash your plant with it to kill the pests. You can also prevent any infestations in the future by spraying your plant with a neem oil spray.

Final Thoughts

Chrysanthemums, or mums for short, are beautiful plants that are extremely popular as they come in such a wide variety of colors.

Unfortunately, this plant can have its fair share of problems turning the plant brown. Trying to find the cause of this issue can be difficult, but if you go through all the possible causes on this list, you should easily find the cause and save your mums!

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