Why is My Coleus Turning Green? (Prevention and Solutions)

By | Updated May 5, 2023

Your coleus plant is turning green or losing its color due to insufficient light exposure. Coleus plants require bright, indirect light to maintain their vibrant color, so they will turn green if they don’t get enough light. Moving the plant to a brighter location or providing artificial light can help prevent color loss.

Coleus is a popular houseplant with vibrant and colorful foliage that can instantly brighten up any home.

But why is it that sometimes, the leaves of your coleus start to turn green?

This article will explain why this might happen and what you can do to prevent it.

We’ll discuss why coleus turns green, possible causes, and solutions so you can have the beautiful plant you desire.

Understanding Coleus Coloration

Coleus plants are known for their vibrant colors and striking hues, but why is your coleus turning green? The answer lies in understanding why coleus produces its unique range of colors in the first place.

Coleus plants produce their unique colorations thanks to a combination of genetics and environmental factors. Genetics determine the type of pigments that will be produced in the plant, while the environment affects where and how much pigment is expressed.

Plant color is the result of pigments, specifically anthocyanins and carotenoids.

Anthocyanins are responsible for coleus’ blues, reds, and purples. Carotenoids, on the other hand, create more yellow-orange hues.

The balance of these two pigment types determines what coloration will be expressed in a coleus plant.

Light, temperature, and soil nutrition can all influence the production of pigments in coleus. When these environmental factors are not properly balanced or adjusted, it can cause the plant to lose some of its bright colorations.

It is important to understand why your coleus is turning green to provide proper care for your plant.

Common Causes of Coleus Turning Green

Identifying why your coleus is turning green is the first step in properly caring for it. Here are a few of the most common causes why your coleus might be turning green:

Lack of Light

When coleus plants don’t receive enough light, they will start to turn green as a means of preserving themselves. This is because these plants rely on the light they get from the sun to create their vibrant colors.

Without light, coleus plants cannot photosynthesize properly and, therefore, cannot produce the pigments needed for their bright hues.

Their leaves respond by changing color to absorb more of the available light, so coleus left in the shade may eventually become completely green.

It’s an amazing adaptation that keeps coleus looking their best, even in less than ideal growing conditions!

Temperature Fluctuations

Coleus plants are a bright, inviting addition to any garden, but why do their leaves turn green when temperatures fluctuate?

A coleus plant tends to thrive in warmer climates with daytime temperatures between 60 and 75 degrees Fahrenheit.

When outdoor temperatures dip too low or rise too high for long periods of time, coleus leaves undergo a process to protect them from further damage.

During this process, the coleus’ natural pigments fade, and its chlorophyll content increases, which causes its leaves to turn green. The more chlorophyll a plant has, the stronger it will be.

This is a great defense mechanism that allows coleus to survive during temperature fluctuations and continue being the eye-catching beauties they are in our gardens!

Lack of Proper Nutrients

If you’ve ever grown coleus plants and noticed yellow leaves, the culprit is likely iron deficiency.

This problem can occur even if coleus plants are given plenty of water and receive adequate amounts of sunlight.

Coleus leaves turn green because of the plant’s inability to absorb sufficient quantities of iron from the soil.

Iron plays an important role in regulating photosynthesis. When it isn’t present in adequate amounts, coleus leaves won’t perform their photosynthetic functions as well as they should, leading them to turn a lighter shade of green or even yellow.

For this reason, it’s essential to regularly check the potting soil where coleus is grown and ensure its iron concentration remains high. Doing so will ensure that coleus always looks its best!

Natural Aging Process

When a coleus plant is young, its leaves are usually vibrant and multicolored.

As it grows older, the once vibrant colors begin to fade away until, eventually, the coleus leaves will turn pale green. This natural process of aging is the result of maturity within the coleus.

The coleus has adapted this change for its own purpose, as green foliage provides essential protection from disease and overexposure to direct sun.

So when coleus leaves turn green in response to natural aging, it’s actually an act of self-preservation!

Treating and Preventing Coleus From Turning Green

Now that we know why our coleus might turn green, we must learn ways to prevent and treat this issue. The most important thing to remember is that each plant is different, so what works for one might not work for another.

To prevent your coleus from turning green, it is important to give them the proper care they need. This includes ensuring they receive the optimal light conditions, adequate temperature, proper fertilization, and regular pruning (if necessary).

Optimal Light Conditions

Coleus plants are colorful plants that can brighten up any space, indoors or out. They’re easy to care for, but there are a few things to remember when it comes to light.

A coleus plant prefers filtered sunlight or bright indirect light. If you don’t provide enough light, your coleus will start to turn green.

To prevent this, make sure to place them in a spot where they’ll get plenty of light without being in direct sunlight. One way to do this is to put them near a window that gets lots of sun during the day but isn’t in direct line of sight with the sun. East- or west-facing windows are usually the best options.

When growing coleus outdoors, make sure to provide them with filtered sunlight or grow them in partial shade.

Adequate Temperature

Keeping coleus plants happy and healthy can be done simply by maintaining a comfortable temperature.

The ideal temperature range is between 60 to 75 degrees Fahrenheit to get coleus to show its vibrant colors. If it’s too cold, the coleus may start to turn green as a sign of distress!

Allowing temperatures to drop below 60 degrees Fahrenheit could lead to more issues with the coleus turning a dull hue that makes it look unhealthy.

Therefore, keeping coleus in an area with enough warmth for vibrant colorations is important. To do this, you can move the coleus indoors in temperatures below 60 or provide extra insulation for outdoor plants.

Proper Fertilization

Fertilizing your coleus is important for optimal growth and health. When fertilizing, use a fertilizer containing the essential macronutrients: nitrogen, phosphorus, and potassium.

These nutrients are necessary for the plant to stay healthy and vibrant. Additionally, fertilizers containing iron can help prevent coleus from turning green.

Iron ensures the coleus’s leaves stay dark and rich in color, so it’s important to regularly fertilize with an iron-rich fertilizer to prevent your coleus from turning green due to a lack of iron.

Fertilize coleus plants during the growing season (spring through summer) once every two weeks for optimal results.

Regular Pruning

Coleus plants need regular pruning to maintain their vibrant shades.

Pruning coleus will also ensure a healthier plant as it prevents coleus from becoming leggy and enables more room for the coleus to get more light, promote more growth, and develop its grander leaves.

To do coleus pruning properly, start by snipping off any dead or diseased leaves—this helps the affected areas heal and improves its overall look.

Next, make sure to remove stems that are too long or overly bushy by cutting at an angle.

If green leaves have started to grow, removing them is best to make way for more vibrant leaves.

Regular pruning helps the coleus stay healthy and increases its chances of staying colorful instead of turning green.

Be sure always to have sharp garden scissors on-hand when pruning coleus. Cutting through coleus with dull scissors could potentially damage the plant more than help it.

Lastly, remember that coleus pruning is best practice before each flowering season to guarantee lovely flowers from a healthy coleus plant!

Final Thoughts

Whether you’re a newbie or an experienced gardener, there are times when your coleus may turn green.

Fortunately, it is usually easy to fix once you understand why it happened in the first place!

With a little love and attention, you can get your coleus back to its colorful glory.

Remember that having a green coleus plant is not the end of the world, but if you want your plant to be its colorful best, following these tips should help.