Geranium leaves turning yellow can be truly worrisome! However, we have listed the most common causes and easy fixes to help you out!
Geraniums are known for their brightly colored ruffled blooms set against a contrasting lush backdrop of healthy foliage. So, if your geranium leaves are turning yellow, bring them back to the pink, or in our case, green, of their health with our guide!
We identify common causes, solutions, and tips to keep your geraniums healthy. Read on to find out!
Types of Geraniums
Let’s first examine different types of geraniums and their specific needs before discussing the causes of geranium leaves turning yellow. A novice gardener might find it difficult to distinguish between the different types of geranium, making it harder to get to the root of the yellowing-leaf problem.
True Geraniums are hardy perennials belonging to the geranium genus, with symmetrical blooms of five identical petals and a low and compact growth habit.
Zonal Geraniums, also known as regal geraniums, are tender perennials belonging to a completely different plant family—pelargoniums! These imposters have flowers with 2 upper petals and 3 lower petals and a varied growth habit, including upright and trailing forms.
What’s the big deal? This minor difference plays a huge role in why geranium leaves turn yellow. While it is natural and normal for our geranium mimics (zonal) to see their leaves turn yellow as part of their natural aging process, the true geraniums tell a different story. Let’s dig in.
Why do Geranium Leaves Turn Yellow?
1. Overwatering
Geraniums have adapted to slightly dry and arid environments. Drowning them with water will only harm these hardy bloom makers, disrupting and stunting their growth, and causing their leaves to yellow. Before planting your geraniums, use well-draining soil in a pot that allows ample seepage.
And only water if the top inch of soil is dry.
2. Underwatering
Alright! That doesn’t mean you leave them thirsty and dehydrated! If the tips of the leaves change into a shade of yellow before the rest of the foliage, then your geraniums are mostly likely parched. Feel free to quench its thirst as and when it says so, and ease up on the watering as the top layer gets sufficiently moist.
The key is to listen to your geraniums. Pay attention, and it will bounce back to health.
3. Lack of Sun Exposure
Geraniums flourish with 6 hours of direct sunlight. Anything below that can change the leaves’ color palette, even turning yellow. Move the plant to a sunny spot, and give it space. Remove obstacles that may be shielding it from ample light, such as overhead hangings and dense foliage of surrounding plants.
4. Too Low or High Temperatures
If your leaves look a little dull in winter, it’s natural, and your geraniums are simply hibernating, as do other perennials. But if this sleepy attitude persists in warmer months, pay heed. Your geraniums are mostly likely affected by cold air through an air conditioning vent, or other chilly source.
On the flip side, high temperatures also pose a threat to these plants. A sudden gush of warm air or the temperatures soaring high can leave the foliage pale and yellow, even brown, leading to plant death, if left unattended.
So, once you’ve struck out watering and sunlight from the list of causes if your geranium leaves still turn yellow, it’s time to move the plant to a warmer spot in the house. Try an east-facing windowsill or a cozy corner in the kitchen.
5. Lack of Essential Nutrients
Nutrition also plays a role in giving geranium leaves its rich green hue. It needs magnesium to produce chlorophyll, the green pigment that aids in photosynthesis. Iron, sulfur, and zinc deficiency can also lead to yellow leaves.
Once you’ve identified this particular cause of nutrient imbalance after eliminating all the obvious culprits, use a balanced fertilizer rich in micronutrients sparingly. The key word is sparingly, as geraniums don’t usually need very rich soil, and too much nutrition can actually hurt its growth.
6. Pest Infestation
Now come the pesky, uninvited, invisible invaders! Southern bacterial wilt and bacterial blight are forerunners in causing geranium leaves to turn yellow.
Southern bacterial wilt usually affects plants in the nightshade family but also mess up warm-weather geraniums. Here, its leaves will slowly turn yellow, but before you know it, it will spread and infect even plant debris and the soil. So you have no choice but to get rid of the entire plant and its remains from the area.
Bacterial Blight is easier to detect as the yellowing occurs in spots. If the leaves have quarter-inch-wide sunken watery spots, then promptly dispose of the plant. This disease is highly infectious and will cause the plant to turn yellow, wilt, and die, and in severe cases, it also leads to the darkening of the stems.
7. Overfeeding the Plant
A common mistake made by inexperienced plant parents is being overprotective! Now, where have we heard that before? But seriously, in your state of concern, don’t overdo the fertilizers! They can lead to salt buildup in the medium and are likely the reason for the yellowing of geranium leaves.
If this is the reason for the leaves’ change in color, quickly increase the watering frequency. This will help the plant wash out excess chemicals and protect its roots as well.
