Hellebore leaves turn yellow when the plant is stressed by an environmental factor. Inspecting the plant and its living conditions to figure out the exact cause of the discoloration is key to fixing the problem.
The most common causes of yellowing hellebore leaves are light issues, soil type, overwatering, underwatering, temperature changes, overfeeding, pests and disease.
In this article, we will discuss the different causes of yellowing hellebore leaves and how to remedy each one.
Why are my hellebore leaves turning yellow?
Overwatering
Hellebore plants like their soil to be somewhat moist, but that does not mean you can get away with overwatering them. If you let the plant sit in soggy soil for long periods of time, its roots will not be able to take in oxygen and they will drown. The dead roots will become more susceptible to pathogens, such as opportunistic fungi and bacteria. This condition is called root rot.
Root rot happens when the infection in the roots moves up to the plant’s stem and leaves. The plant’s leaves will turn yellow, then brown, and fall off. If you are not able to catch the root rot in its early stages, you might not be able to salvage the plant at all.
If you are able to catch the rot in its early stages, you may be able to save the plant. Take it out of the pot and wash the soil from the roots. If there are any brown and black rotten roots, cut them off using sterile scissors. Let the plant air dry on a tray lined with a paper towel. When the roots have dried up, you can replant it in a pot with drainage holes at the bottom, using well-draining soil.
The best way to avoid overwatering is to know when to water the plant. You can do this by checking the soil: If the top two inches are dry to the touch you can water the plant, but if the top two inches of soil are still wet, check the soil again after one or two days.
Underwatering
Hellebore leaves can also turn yellow when the plant does not get enough water. Like all plants, hellebore needs water for the moisture that it gives the plant as well as to transport essential minerals and nutrients from the soil to the plant. If the plant does not get water for long periods of time, it will choose to sacrifice its older leaves close to the base by withholding resources from them. This is to focus the plant’s limited resources on the younger leaves at the top of the plant. The leaves near the base will turn yellow, then brown, become brittle and eventually fall off.
You can remedy an underwatered hellebore plant by establishing a regular watering schedule. If you touch the soil and it feels dry, water it until all of the soil in the pot has been soaked and the excess water is flowing out of the drainage holes at the bottom. Making sure all the soil is wet is important, so that all the roots can get water.
Light issues
Hellebore plants like to be in partial shade, and if they are placed under direct sunlight for long periods of time, their leaves will turn yellow and even brown due to leaf scorch. They should be placed in a spot where there are trees that will provide them with shade.
If you place the plant indoors, do not place it in an area that gets too much light. If you have no choice, try placing a curtain to diffuse the light and avoid sun damage.
If the plant does not get enough light, on the other hand, the leaves will also turn pale and yellow. During the colder months when sunlight is sparse, you can buy a grow light to help the plant get its required amount of light.
Soil type
Hellebores thrive in soil that has plenty of organic matter and drains water well. Well-draining soil eliminates excess water much more effectively than compact soil such as clay. This helps avoid overwatering by letting the excess water flow to the bottom of the pot and out of the drainage holes so that the soil can dry out better between watering and get aerated.
Hellebores also like their soil to be alkaline, so if the soil on your plants is acidic, try adding lime to neutralize the soil or make it more alkaline.
Temperature changes
Hellebores can tolerate high temperatures fine, but they will need to be taken indoors during the winter because they do not do well in the cold or harsh winds. The low temperatures can cause their leaves to turn yellow.
When the plant is indoors for the winter, make sure there are no hot or cold drafts passing through the area where the plant is located. The warm and cold air constantly hitting the plant will also have a negative effect on it.
Overfeeding
You can give your plant fertilizer in the spring and early fall to encourage growth. You do not need to fertilize it in the winter, because you might overfeed it which can also have a negative effect.
You can try to flush excess fertilizer from the soil by letting water flow through the soil and out of the drainage holes.
Pests and disease
Hellebores are normally tolerant of pests, but can be susceptible to aphids feeding on the sap of their leaves. You can remove the infestation by pruning the affected foliage or by using neem oil. Apply the neem oil to the leaves using a cotton ball. Treat the plant once a week for a month to make sure all the aphids have been killed.
Leaf spot and downy mildew are the most common fungal diseases that infect hellebores. You can use a fungicide to remove these infections.
Make sure you keep the infected plant separate from your other healthy plants, so the pests and disease do not spread.
Conclusion
Hellebore leaves turn yellow when an environmental factor is causing the plant stress. The key to fixing the problem is correctly identifying the cause of the discoloration.
The most common causes of yellowing hellebore leaves are light issues, soil type, overwatering, underwatering, temperature changes, overfeeding, pests and disease.
Image: istockphoto.com / Claudia Cooper