Corn plant leaves turning yellow is a major concern, especially when these leaves also begin to fall off. If you’re experiencing this issue, there’s no need to panic.

Yellowing Leaves - Corn Plant

In this guide, we have gathered information from our top corn experts on what might be causing this problem and how to solve it.

Why Is My Corn Plant Turning Yellow?

Your corn plant might be turning yellow because of underwatering or wrong temperatures, among other reasons. From unfulfilled cultural needs to attacks by external agents, find out what is causing this yellowing in your plant and how to deal with it here.

– Not Watering Your Plant Enough

Corn plants need plenty of water throughout the year. If watered less than required, especially during the hot summer months, the plant’s leaves start turning yellow and brittle, after which they eventually fall off.

– What To Do

You should water your plant at least three to four times each week. Use copious amounts of water each time and allow the soil enough time to absorb all of it. Your pot should have a proper drainage hole of an adequate enough size to let the excess water flow off.

Mulching is another great way to retain moisture in the soil for a long time without overwatering your plant. Use bark chips, grass cuttings, newspapers, etc to cover your soil. These will prevent premature and undue evaporation of water from the soil.

– Cold and Shade

A corn plant with yellow leaves can also be seen during the harsh, cold winter months. This is aggravated by excessive rainfall, which leaves the soil wet most of the time. Your plant finds it hard to access nutrients from the cold, wet soil. As a result, the leaves turn yellow and eventually fall off.

The same thing happens when the corn plant is placed under too thick a shade. Whether grown indoors or outdoors, your plant needs the maximum amount of partially bright sunlight it can get in a day.

– What To Do

If you have planted your corn in a pot, then you’re at an advantage. Simply move your corn plant inside when the weather starts getting too cold. When growing corn plants outside in a garden or a nursery, don’t forget to cover them tightly with plastic or tarp when the frost hits.

Also, make sure your plant has exposure to adequate sunshine even during winters. When kept indoors, place them near an eastern or a western-facing window. These windows provide indirect light that is bright enough for your plant to develop food and keep its leaves green.

– Attack by Pests and Bugs

Your corn leaves turning yellow can be a sign of pest infestation. The pests that commonly attack vegetative plants like corn are aphids, nematodes and earworms. They suck the sap out of the plant, reducing nutrient flow to the leaves.

– What To Do: Preventative Measures

In this section, you’ll learn how to deal with yellowing leaves caused by pests and bugs.

Take extensive preventative measures against pests by checking your plant regularly. Prune and remove old leaves and bark sheaths from the stem as these areas usually serve as the hiding spots for pests.

In addition, protect your pot and the soil around the plant by removing debris and grass from it. Regularly uproot weeds and other critters, and wash your plant with soap and water. This is another great method to get rid of those pesky insects.

– Treating Pests

If your corn plant is turning yellow due to pests, then you need to get rid of them as soon as possible. For insects like aphids, you can remove them physically using a cotton roll or water jet.

A variety of insecticides are available in the market for you to choose from. We recommend you use organic insecticides over chemical ones. Not only are they safer for your plant and soil overall, but they are also pretty reasonable in price.

Reasons Behind Corn Leaves That Yellow

– Disease and Rot

Sometimes, the corn plant turning yellow can turn out to be a pretty persistent problem. You can fix everything from your watering schedule to pest control and yet the problem will keep on getting worse. This means that your corn plant is suffering from a bacterial or fungal disease. The situation requires urgent intervention.

– What To Do

In case of fungal or bacterial rot, you can initially try saving the plant. Remove all diseased yellow leaves and cut off the rotten stem parts. Take out the whole plant from the soil and debride the soggy roots as well. Repot the plant in fresh soil and treat it with antifungal or antibacterial sprays regularly.

Sometimes, a plant may be too far gone to be saved. In such a case, you will have to simply let go of your precious corn plant. Carefully dispose of the whole plant and its soil somewhere where it cannot contaminate the surrounding plants.

We strongly advise against using this diseased plant and its leaves as compost. Doing so will only spread the infection to other plants. For the very same reason, sterilize any instruments that you used on these plants before using them on other plants.

– Simple Old Age

One very common but often understated reason for lower corn leaves turning yellow is old age. A corn leaf on average lives for only two to three years. After this, they naturally start turning yellow. 

It’s best to remove them at this point as it frees up nutrients for younger leaves. You can use these old leaves as compost for your plant instead.

– Herbicide Toxicity

This holds particularly true for ALS herbicides that are much in use these days against not only weeds and plant feeders but also various species of fungi, bacteria and algae.

Excessive and uncontrolled use of these herbicides will cause your leaves to turn yellow and start falling off at an alarming rate. ALS yellowing is most commonly seen in young leaves and foliage.

– What To Do

  • Try to stay away from these herbicides in general and weeding out manually if possible. 
  • Exercise caution when you do have to use them on your corn plant. Always follow the instructions given on the label regarding storage and use.
  • We never use ALS herbicides in the fall season especially. This will not only cause yellow leaves but also affect the further reproduction of your plant.


Corn Plant Turning Yellow? Nutrients Could Be the Problem

Did you know that inadequate levels of certain nutrients could also be causing the yellowing of your corn plant and its leaves? Learn more about this below.

– Potassium Deficiency

Potassium is an essential nutrient that your corn plant needs for its protection and water regulation. A plant that lacks potassium will start exhibiting yellowing of its leaf tips. Some reasons why your plant might be lacking this element are as follows.

Some soils are just inherently deficient in potassium. Regularly check your soil to find out if it lacks this nutrient. Conditions of drought and underwatering will produce potassium deficiency in your corn plant even when the soil levels are optimum. This is because potassium uptake in the plant occurs through the water.

Sidewall compaction is a condition that occurs when plants are buried too shallow in the soil or in too wet soil. It can also lead to your corn plant developing a potassium deficiency.

– What Potassium Deficiency Looks Like

The leaves present on the bottom of the stems are affected by potassium deficiency first. You will notice that these leaves start turning yellow at their tip ends. This yellowing then travels along the margins, eventually turning the entire leaf a shade of rotten brown.

How To Treat Potassium Deficiency

  • Add more organic matter!
  • Reduce the acidity of the soil by adding lime to it.
  • Improving the moisture levels of your soil will also improve potassium uptake by the plant.

– Sulfur Deficiency

Sulfur is also a major nutrient that the corn plant needs for food formation and proper growth. What causes sulfur deficiency in the soil? Find out below.

Frequently heavy rainfall removes sulfur from the soil over time. Using the same soil for crops year after year will lead to a severe loss of sulfur. This condition also occurs when the pH balance of the soil becomes disturbed.

Secure Corn Leaves From Yellowing

– What Sulfur Deficiency Looks Like

In case of a deficiency of sulfur in the soil, the top leaves of your corn plant will begin to turn yellow. The affected leaves will exhibit a greenish-yellow discoloration.

– How To Treat Sulfur Deficiency

Directly adding sulfur or a sulfur-containing compound to the soil will work for at least two to three years. You might need to add in more sulfur in case of heavy rains.

– Nitrogen Deficiency

Your corn plant needs nitrogen to create chlorophyll, which is essential for photosynthesis and food formation. If your leaves are turning yellow, lack of nitrogen can be the reason behind it. Continue reading to learn some common reasons why this happens.

Not fertilizing your plant enough will often lead to a nitrogen deficiency. The same thing happens when you use a fertilizer that doesn’t have adequate levels of nitrogen in it.

Adding too much organic matter into the soil will produce yellowing of corn leaves. This happens because organisms in the soil use up all the nitrogen to break down this organic matter. Consequently, not enough nitrogen will be available for your plant to consume.

– What Nitrogen Deficiency Looks Like

The lower leaves on your corn plant will start to yellow first. This discoloration will appear first at the leaf tips before traveling along the region in a V-shape. Eventually the whole leaf wilts and falls off.

– How To Treat Nitrogen Deficiency

  • Fertilize your plant with a nitrogen-rich fertilizer at least once a month during its growth period.
  • Add manure and compost to the soil on a regular basis.
  • Adding coffee beans to the soil will also boost its nitrogen levels.

Corn Plant Leaves Are Turned Yellow


What fertilizer fixes yellowing corn plant leaves?

A balanced nitrogen-based fertilizer can help fix yellowing corn leaves by providing the necessary nutrients for healthy growth.

Should I pinch off yellow leaves from corn plants?

It is generally recommended to pinch off yellow leaves from corn plants as they may indicate nutrient deficiencies or diseases.

How do I stop yellow corn plant leaves?

To stop yellowing corn plant leaves, ensure proper watering, address nutrient deficiencies, and monitor for pests or diseases.


You have learned a good deal about why your corn plant might be turning yellow. Given below is a brief recap of everything we have discussed so far.

  • Underwatering the corn plant remains the foremost reason why its leaves turn yellow and fall off.
  • Water this plant at least three to four times each week.
  • A cold, wet soil during the winter months makes it hard for your plant to access nutrients. This leads to the leaves turning yellow and falling off.
  • Your corn plant leaves will turn yellow when placed under too much shade. Choose an eastern or western-facing window for them.
  • Pests such as aphids, nematodes and earworms suck the sap out of your plant. Eventually, the leaves will turn yellow and die off.
  • Take preventive measures against insects by regularly inspecting your plant.
  • In case of a bacterial or fungal infection, saving your plant might be nearly impossible. Dispose of the diseased plant appropriately and never use it as compost for other plants.
  • Lower corn leaves turning yellow can just be due to natural old age. Prune them and use them as compost.
  • Strictly avoid using ALS herbicides to treat pest problems of your corn plant.
  • Nutrient deficiency is a major reason why your corn leaves might be turning yellow.
  • Perform a soil test on your plant to see if it lacks essential nutrients like potassium, nitrogen and sulfur.

You no longer need to worry about your corn plant turning yellow. Follow our guide to solve all your corn problems right away.

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