Troubleshooting Dying Mums

Chrysanthemums, often referred to simply as Mums, are popular fall plants. Available in an array of Autumn-themed colors, Mums are generally considered to be low maintenance. Dying Mums are a result of not giving your plant the growing environment it needs to thrive. Thankfully, Mums are a hardy plant and will often bounce back when the issues are corrected. 

Why Are My Mums Turning Brown?

There are several reasons that can lead to dying Mums. It may take a little investigating to figure out the cause(s) of your failing plant, but if you’re wondering how to bring Mums back to life these common issues are a good place to start. 

Dead Mums: Sunlight Issues

Too much direct sunlight will cause scorching of your Mum’s leaves, causing your plant to turn brown. As a fall plant, Mums prefer cooler temperatures and will dry out quickly if overexposed to high heat and sun. Do give your plants some sunlight, about six hours per day, but ensure those hours aren’t in the mid-afternoon if you live in a hot climate. Instead, aim for several hours of morning sun which will benefit the Mums but not overwhelm the plant.

Alternately, too little sunlight stifles the Mum’s ability to perform photosynthesis. This inability to turn sunlight into nutrients effectively starves the plant and it will begin to turn yellow and, eventually, brown. Aim for those six hours of sunlight in warm, but not hot, temperatures.

Soil for Mums

Heavy soil with poor drainage will easily become waterlogged. Soggy soil is detrimental to a Mum’s roots and will eventually cause root rot if the issue is not corrected. One of the first signs of poor soil is a yellowing plant. The yellow leaves will turn brown and continue to decline unless the plant’s soil is amended. Add one part sand or peat moss to two parts of a quality potting soil. MIx the parts together well and repot your plant in this new, lighter soil. 

If amending the soil doesn’t correct the issue, there may be a lack of nutrients in your soil as well. Correct poor soil quality in two ways: by mixing in one part of compost into the soil or feed your plant with a balanced, slow-release fertilizer as per the product directions. Either of these methods will boost the soil’s nutrients and will help the Mums recover if a lack of nutrients was the issue. 

Dying Mums: Watering Issues

Overwatering is a common cause of Mums turning brown or dying. Mums prefer consistent moisture but do not do well growing in soggy soil. When soil is consistently soggy, the plant’s roots become saturated with water and lose the ability to absorb water and nutrients. As a result, your plant actually becomes dehydrated and malnourished. If allowed to continue, the plant will eventually die as its root system begins to rot. 

Correct overwatering by decreasing waterings immediately. Insert your finger into the soil regularly and do not give the plant water again until the top 1 to 2 inches of soil feels dry. When you water, stop once the soil is consistently moist and the water begins to run out of the pot’s drainage holes. Once the soil has drained any excess water into the pot’s saucer, discard the excess water. Continue to perform the moisture check with your plant’s soil until the top 1 or 2 inches is again dry. Use this as a guide to create a regular watering schedule. 

On the other end of the spectrum, underwatering your plant will also cause your plant to suffer and turn brown. A consistent watering schedule, guided by regular soil checks, will prevent this issue. 

Dying Mums Due to Root Rot

If changing your plant’s watering schedule does not correct the issue, and your Mum is still dying, check the plant’s root system for rot. To assess the presence of rot, and the amount of damage present, gently remove the plant from its pot and inspect the roots. Use a pair of sharp and sterile shears to remove any of the roots that appear dark and mushy. Next, create a mixture of two parts water and one part hydrogen peroxide in a spray bottle. Generously spritz all the remaining roots to kill any remaining bacteria. Finally, remove all the soil from your pot and throw it away. Clean out the pot with soap and water, and repot your Mums with fresh soil. 

Diseases That Kill Mums

Mums with poor health from improper care are more susceptible to disease. There are two main types of diseases that can attack your plants–funguses and bacteria. It’s important to know which you are dealing with so you can treat the issue properly.

Fungal Issues

Fusarium oxysporum, Alternaria spp., Septoria spp., and Cercospora chrysanthemiis are the common fungi that will cause issues on your Mums. The Fusarium fungus will start in the roots and will spread to the vascular tissue of the plant. The result is yellowing, browning, and wilting of the leaves. The plant will also suffer from stunted growth and will struggle to bloom. Other fungi present on the plant’s leaves causing spots known as leaf blight. You can distinguish between Fusarium and root rot by looking for how much of the plant is affected. If only one part is showing signs of stress, it’s likely Fusarium. Root rot will affect the entire plant. 

To treat fungal issues, prune all damaged and affected leaves using sharp and sterile shears. Next, treat the plant with a fungicide as per the product’s directions. To inhibit the growth of new fungi in the soil raise the soil’s alkalinity to between 6.5 to 7.0. The easiest way to raise the alkalinity of soil is to add baking soda. Use a soil test kit for accuracy. 

Bacterial Issues

The most common bacteria is Pseudomonas cichorii, which causes dark-brown spots on the plant’s leaves. These spots will often look wet, though they can dry out, turn lighter, and crack as the issue progresses. Treat the issue by pruning the affected areas of the plant with sharp and sterile shears. Spray the entire plant with a copper hydroxide spray as directed. 

Mums Turning Brown After Being Moved

If a previously healthy plant begins to show signs of distress shortly after being brought home from the garden center or moved to a new location, it may just be the plant acclimating to its new environment. Ensure the plant is receiving the correct amount of sun, water, and temperatures to rule out more serious issues. Allow the plant to acclimate to its new surroundings and it should begin to rebound in a week or two. 

Dying Mums can be a result of several factors. When you notice your Mums turning brown or looking stressed, it’s important to troubleshoot the cause as quickly as possible so limit the amount of damage incurred. In most cases, if caught early, care issues can be reversed and your plant will return to normal in time. 

Dying Mums FAQ