If you’re like most gardeners, you probably spent the winter months anxiously waiting to get your hands on some pansies. Now that they’re finally in bloom, you may be noticing that their leaves are starting to turn yellow.
Don’t worry – this is a common problem, and there are ways to avoid it in the future. In this article, we’ll discuss what causes leaves to turn yellow on pansies, how to deal with the issue if it arises, and some tips for keeping your plants healthy.
About Pansies
Pansies are a type of flowering plant that is part of the Viola family. They are known for their brightly colored flowers and their ability to bloom in cooler weather —which is why they’re also called winter flowers.
Pansies are typically planted in the spring, but they can also be planted in the fall in some parts of the country.
When pansies first begin to bloom, they often have vibrant colors and look very healthy. However, as time goes on, their leaves may start to turn yellow. This is usually caused by a lack of nutrients, specifically nitrogen.
Nitrogen is an important element for plants because it helps them create chlorophyll – which gives leaves their green color. Without enough nitrogen, leaves will turn yellow and eventually die off.
So essentially, what causes the leaves of pansies to turn yellow is whatever is preventing them from getting the nitrogen they need. There are many different potential causes for leaves turning yellow, which we will cover below.
1 – Overwatering
The most common cause of yellow leaves on pansies – or any plant for that matter – is overwatering. This is especially common among new gardeners and plant enthusiasts.
It’s easy to want to care for your plants every day, but the reality is that they don’t all need your attention on a daily basis, especially not when it comes to watering. Unless you’re using a soil that drains too quickly, your pansies will only need to be watered every few days.
Proper potting soil will retain just enough water for your pansies to comfortably drink whenever they need to without drowning in soggy soil. When the soil is too wet, the plant may absorb more water than it can handle, literally drinking itself to death.
In some cases, leaves begin to turn yellow, as the cell walls burst from having taken in too much water. This will begin to appear as yellow spots, but will soon spread until the entire leaf has turned and wilted.
To properly water your pansies, limit watering to only when the top inch of soil is dried out. Make sure you use soil that drains, but not too much.
2 – Root Rot
When the soil is constantly wet, the roots can’t get enough air, and this can lead to root rot – a condition that causes the leaves to turn yellow and eventually die.
Root rot is exactly what it sounds like – roots rotting. When the soil retains too much water, the roots can’t get enough oxygen and they will start to die. As the roots die, fungus begins to take over, further suffocating the plant.
It’s crucial to take care of root rot as soon as possible, as it will only continue to spread until the plant is completely dead, and probably move to other plants sharing the same bed of soil.
To get rid of root rot, you need to diagnose it first. To diagnose it, you’ll need to remove your pansies from the soil, and closely inspect their roots. Healthy roots should be white and springy. Rotten roots will be black and soft. If any part of the root system is beginning to rot, you will have to take steps to remove it.
With a pair of gloves and sterilized gardening shears, trim away all rotten parts of the plant. Once this is done, sterilize the root system using a mixture of water and hydrogen peroxide in a ratio of 10/1 (10 parts hydrogen peroxide, 1 part water).
Make sure that you also provide new soil, and a sterilized pot before replanting your pansies.
3 – Too Much Light
Pansies need around six hours of sunlight a day, but too much sun can also cause their leaves to turn yellow.
If the leaves are turning yellow and falling off, it’s possible that they’re getting too much light. This usually happens when pansies are planted in an area that gets direct sunlight for most of the day.
The sun will literally scorch the leaves, causing them to turn yellow and eventually die. Too much light will also prevent your pansies from blooming, so it’s important to keep a close eye out when it comes to placement.
To prevent this from happening, you should choose a spot for your pansies that gets partial sun – around six hours of sunlight a day.
4 – Pests
In some cases, pests may be responsible for leaves turning yellow on pansies. Pests such as aphids and thrips love to feed on plants and can quickly cause damage, which will show up as yellow leaves.
These pests are small, but they can do a lot of damage if left unchecked. If you think that pests may be the problem, you should inspect your pansies closely for any signs of insects.
Aphids are small and pear-shaped with long legs, while thrips are tiny and winged. If you see any pests on your pansies, you should remove them immediately.
The best way to get rid of aphids is to blast them off with water from a hose. Just make sure that the water pressure isn’t so high that it damages the plant.
The best time to do this is in the morning so that the plant has enough time to dry out before the sun goes down. For thrips, you can use an insecticide designed specifically for thrips, or introduce predatory bugs such as minute pirate bugs or a green lacewing.
Other Causes
Some other causes of yellow leaves include nutrient deficiencies or diseases. Some common diseases include Alternaria pansy leaf disease, and necrotic impatiens spot virus.
The former is caused by infected seeds, and is difficult (if not impossible) to detect. It will begin as yellow spots on the leaves, and progress to darker brown spots, with the centers of the spots eventually dropping out.
Necrotic impatiens spot virus causes bull’s eyes, dark ring spots, stem lesions, and leaf lesions that eventually cause the plant to die.
What Can Be Done
If you’re seeing yellow leaves on your pansies, the first thing you should do is assess the situation. Make sure that the plants are in a sunny location with well-drained soil, and water them sparingly until the problem is resolved.
If it’s a warm day, you may not need to water them at all. You should avoid fertilizing your plants when they’re under stress, as the excess nutrients may exacerbate the problem.
Final Thoughts
If your pansies leaves are turning yellow, there are a few possible causes. The most common cause is incorrect watering, but too much light or pests can also be to blame.
In some cases, diseases may also be the cause. If you think that your pansies are suffering from a disease, the best course of action is to remove all affected parts of the plant.
Otherwise, you should be able to resolve the problem by making sure that your plants are getting the correct amount of water and sunlight.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.
Before you go: Now is the perfect time to start tracking your gardening progress, and I created a garden journal to do exactly that. Click the image below to see it in action and to get your own copy.
