The cast iron plant is a common houseplant with beautiful dark green leaves. These plants are fairly easy to take care of but they do have one major weakness – yellowing leaves.
In this post, we will talk about what causes cast iron plants to turn yellow and how you can treat them. Let’s get started!
Why Is My Cast Iron Plant Turning Yellow?
Your cast iron plant is turning yellow because the plant has been overwatered, it hasn’t received enough light, or the environment is causing stress.
I will now go into more depth on the most common causes of yellowing leaves on a cast iron plant and what you can do about them.
Yellow Cast Iron Plant from Overwatering
The most common cause of yellowing leaves on a cast iron plant is overwatering. If youâ€™re not careful, the roots will quickly become waterlogged and begin to rot.
They need moist but well-draining soil, which means that allowing them to sit in water for long periods of time can be deadly!
Water your cast iron plant only when the top inch of soil feels dry or add a thick layer of mulch around its base so it requires less frequent watering. You can test the soil by sticking your finger in the soil up to the second knuckle. If it feels moist, wait until it dries out before watering again!
In such a case that root rot has already taken hold you need to take some steps to save your plant. Start by pruning any rotten roots and discarding them away from all plants. Next, allow the plant to dry out, before repotting it into fresh soil that drains well.
Moving forward, be strict with the watering schedule. I tend to water a cast iron plant every few weeks. They can survive for a long time without water, so tread carefully.
Yellow Cast Iron Plant from Too Little Sunlight
Another common cause of yellowing leaves on a cast iron plant is lack of sunlight. When the plants get too little light their stems will start elongating and stretching toward any available source, which causes them to become tall and leggy with long thin leaves at the top.
Just like other ferns or houseplants that require lots of bright indirect light, your cast iron plant needs more than just one hour of sun per day!
If youâ€™re not sure if it gets enough sunlight, then place it near an east-facing window where no curtains are blocking out morning or afternoon sunshine.
You can also use grow lights (Amazon link), which are affordable and easy to use, especially if your cast iron plant rarely receives any sunlight from natural sources. I use them on nearly all of my plants during winter and in certain rooms around my house.
Yellow Cast Iron Plant from Stress
The final common cause of yellowing leaves on a cast iron plant is caused by stress. This could be due to temperature fluctuations, drafts from windows or fans, and other environmental factors that put the plant under duress.
To make sure your cast iron plant doesnâ€™t develop these issues, keep it away from any artificial heating and cooling sources, like vents or radiators. Also, avoid placing it near large windows or sliding glass doors where youâ€™ll get lots of drafts.
In fact, I remember this happening to one of the plants I kept on top of my TV. Basically, the heat from the TV caused temperature fluctuations that stressed out the plant.
One of the worst mistakes many people make is to repot their stressed plant into the new soil. However, this can make things worse and cause the plant to go into shock. This is why you should only repot a plant when absolutely necessary, like root rot.
Yellow Cast Iron Plant FAQ
As cast irons are the easiest plants to take care of, I’ll go through some of the most frequently asked concerns regarding yellowing leaves.
Should I cut yellow leaves off my cast iron plant?
Yes, these leaves can’t be saved, so you have to cut them off. This will help you save the plant and avoid bacterial infection.
Will too little light cause my cast iron plant to turn yellow?
Yes, cast irons need plenty of light to prevent yellowing leaves. However, they can survive in a dark room with the help of artificial grow lights. They are also one of the hardiest plants around, so don’t worry too much.
Will too much water cause my cast iron plant to turn yellow?
Yes, overwatering will cause the roots to rot and ruin your plant. Thus, you should take extra care while watering it.
Will yellow cast iron plant leaves turn green again?
No, it is unlikely that the yellow leaves will turn green again. However, the good news is that the new foliage will be green if you give the plant the correct care.
In conclusion, yellowing leaves on a cast iron plant can be caused by lack of sunlight, overwatering, root rot or stress. It’s important to monitor the light, watering, and temperature to avoid these issues.
Keeping your plant healthy is not too difficult – just make sure to follow the basic cast iron plant care rules. Doing this will keep the plant green and thriving for years to come!
Thank you for reading. Please feel free to leave a comment or question below and I’ll reply as soon as possible. Also, feel free to check out my other articles about caring for these beautiful plants.
Tim is an avid gardener from the UK. He was the founder of PlantCarer.com from 2021 to Sep 2023. He sold PlantCarer.com to Aaron. He has since started his own business called Seed To Supper, which provides new gardeners all the materials you need in a box (pots, seeds, compost and instructions) to grow your own delicious and nutritious vegetables and herbs from start to finish – no garden required.