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Corn is one of the edible plants you can grow whether outdoors or in a container. But while growing some I found that a plant is turning yellow. I wanted to do some investigation to find the problem and a solution.

Your corn plants are turning yellow because they have a nutrient deficiency. They may also turn yellow due to cold weather, dehydration, and root rot due to overwatering. Some of these problems can harm the plants but some can be reversed with addition of nutrients and right amount of watering.

Of course, you will likely need to complete a process of elimination to determine which of these causes is the root cause for your corn plant’s yellowing. While there are several ways to complete this process of elimination, it is important to use your common knowledge to best inform your direction. To learn more about how to help your yellowing corn plants, continue reading.

What Causes Corn Plants to Turn Yellow?

Yellow corn is relatively typical and likely what you imagine when you think of grinding or buttering up a nice ear of corn. However, the corn plant itself (as in the outside green casing) should not be discolored in any variety.

Discoloration from the standard green coloring on the outside of a corn plant can indicate an unhealthy plant. It is important to know what is causing your corn plants to turn yellow in order to be able to resolve the issue.

There are a few causes that will result in your corn plants turning yellow. Consider the following:

Nutrient Deficiency

Nutrient deficiency is one of the most likely causes of your corn plant turning yellow. While a healthy corn plant will remain green on the stalk, a nutrient-deficient corn plant will demonstrate discoloration in a spotty, streaky, or relatively solid spread in discoloration.

Nutrient deficiency on your corn plant that is causing it to turn yellow could be caused by a deficiency in a variety of nutrients, although nitrate is the most common. To resolve this, you will need to identify which nutrient your corn plant is deficient in.

Likely, you can do this by a visual examination of the corn to determine the pattern and scope of the coloration (and discoloration) on the corn. Plus, you can perform a soil test to test and confirm any deficiencies in the soil.

Often, when a corn plant is experiencing a nutrient deficiency that is causing it to turn an abnormal color, this is because the soil that it is planted in does not contain enough of this specific nutrient. When this is the case, the soil can be replaced or supplemented with fertilizer that contains this specific nutrient.

Other causes of nutrient deficiency include nematodes and disease which can harm your corn plant’s ability to absorb the appropriate nutrients that it needs to remain alive. When these options are the case (especially compared with nutrient deficiency coming from the limited nutrients in the soil), your corn plant is likely not going to fare well in the end and might end up being spoiled for good.

So, if you are considering a nutrient deficiency as the most likely culprit to your corn plant’s yellowing leaves, then it is important to run a soil test and figure out if the soil itself is limited in nutrients and therefore not able to provide them to your corn plant.

Otherwise, it could be another cause that is inhibiting the plant from absorbing the nutrients that are coming from nutrient-rich soil. Testing the soil and examining the corn for how it is discolored will help you to determine the root cause in order to address it and get back to your regularly-colored and well-maintained corn plant.

Cold Weather

Cold weather is another culprit that could be causing your corn plants to turn yellow. Perhaps you have been enjoying the standard temperatures of the summer when all of a sudden the brisk cool fall/winter days begin to approach you unexpectedly. Unfortunately for your corn, this can cause a few issues with discoloration indicating a hindrance to proper growth.

Even if your corn plant experienced cold weather for just one day, you might begin to see a bit of yellowing or discoloration from the standard green color that should be on the outside of your corn husk.

Often, the reason that the cold weather is harming your plants goes right back to nutrient deficiency. Unfortunately, the temperature of the soil affects the ability for the plant to grow. Typically, when the corn plant is growing healthily in a container or in your yard, it is able to absorb proper amounts of nitrate (among other nutrients) from the soil.

When the soil is chilled, though, it can become difficult for the corn plant to soak these nutrients up. This can cause your corn plants to yellow and you to become frustrated. If you believe that this is the case, then be sure to either move your plants in their containers to a slightly warmer location or monitor for the nutrient levels in your soil and see if your corn plants are affected.


Dehydration is yet another cause that could be resulting in your corn plant turning yellow. Just like you and I need plenty of water and hydration to maintain and propel our health, a corn plant needs the same. When temperatures get too warm or you are not watering your corn plants enough, then they can become dehydrated resulting in yellowing and dying corn plants.

One way to test for dehydration is to observe the soil that your corn plant is in. While this can be easier to do in a clear container, you might have your corn plants in your yard resulting in the need to dig up a bit of the soil for a closer look.

Hydrated soil for your corn plant (and other plants) should not have visible standing liquid. If this is the case, your soil is likely not absorbing water meaning it is likely not healthy and will not be able to add much value to your plants. On the other hand, if your corn plant is standing in rock-solid, cracked dirt, then it is safe to assume that the soil is not hydrated enough.

Appropriately hydrated soil should be moist about 1-2 inches below the surface. This should be the same throughout a wide area- wide enough that the corn plant would be able to reap the benefits of the hydrated soil.

If you are concerned that your soil is not taking enough water, then be sure to take a closer look at why it might not be absorbed in the first place. Then, either by replacing the soil, working it until it is able to take on more water, or finding another alternative, be sure that the soil that is harvesting your corn plant is adequately providing hydration to your corn.

Root Rot (Caused by Overhydration)

Root rot is another reason that your corn plant could be turning yellow- and this reason could become very difficult to reverse. Root rot is caused by overhydration of the plant often found when there is residual water left standing near the plant.

This cause will mean that your yellowing corn plant does not have a sustainable way to soak in the water that is being poured onto the plant. So, water remains standing as a puddle on top of the soil.

While you might think that is difficult to over hydrate a corn plant, this is not the case. In fact, it can be one of the leading causes in your corn plant turning yellow and being unable to grow. When this is the cause of your corn plant turning yellow, you will likely have to toss the plant as it will have (more likely than not) sustained too much damage to recover.

Because of this, it is important to take preemptive steps to prevent the overhydration of your corn plants. In doing so, be sure to provide plenty of drainage for your corn plants whether they are in containers or in the ground.

Additionally, use high-quality fertilizer that is rich in nutrients and can also drain well. Preferably, using one with peat will help to evenly distribute the moisture. Along with this, be sure that you are watering your corn plants about once per week unless the temperatures exceed 85 degrees Fahrenheit in which case you might need to water twice per week.

Always monitor the environment in which your corn plants are growing to determine what the cause of their healthy or unhealthy growth might be. Then, make adjustments accordingly.

Here are some of my favorite container gardening tools

Thank you for reading this post. I hope it helps you with your gardening needs. I’ve listed some tools below that can help you with container gardening. These are affiliate links so I’ll earn a commission if you use them.

Gardening Gloves – I find the Pine Tree Tools Bamboo Gardening Gloves really good for both men and women. It’s made from bamboo so helps absorb perspiration. They are also comfortable and fit very well.

Containers – You know picking the right container is crucial for your container gardening. I’ve written a detailed post on the best containers you can choose from. If you’re happy with a plastic container, you can check out the Bloem Saturn Planter.

Watering Can – This is a must-have tool when you’re growing plants in pots or grow bags. It helps to water the potting soil without splashing on the foliage. The Kensington Watering Can is stylish, strong, and can provide precision when watering potted plants.

TrowelGarden Guru Trowel is my favorite because it’s durable and comfortable to use. My gardening friends really love having a trowel because they use it for digging soil, mixing fertilizer, moving seeds, leveling out the soil, mixing compost or mulch, and also dividing tubers

Bypass Pruner – I really like the Corona Bypass Pruner because it’s durable and gives a clean cut that helps plants recover faster. If you’re looking for something cheap, get the Fiskars Bypass Pruner that is really good as well.

To see an extensive list of the best container gardening tools gardeners recommend, check out this resource that I made for you.