Why Are the Gardenia Flowers Turning Yellow? [5 Causes]

Creamy-white blooms of gardenia are the actual beauty of its. Gardeners work hard and take good care of gardenias for enjoying the pin-shaped white flowers with a sweet fragrance.

But all of your hard work will be worthless when you notice that the beautiful white blooms are turning yellow quickly and falling off. Sounds sad, right?

Don’t worry! It is not happening without the causes. Of course, some reasons behind the problem.

It may happen because of environmental stress, over and under-watering, nutrient deficiency, and soil pH.

And in this article, I will discuss the ins and out of the causes and solutions of gardenia yellow blooms. So, without losing your time, let’s learn why are the gardenia bush flowers turning yellow-

The lifespan of Gardenia Flowers

Before diving into the main topic, you should know that flowers are ephemeral. Gardenia flowers turn yellow when they are dying. 

Now the question is, how long gardenia flower last?

Generally, the robust gardenia blooms can survive for 1- 2 weeks. So, if your gardenia flowers last at least one week, then you don’t need to worry about the yellow blooms.

Why Do Gardenia Flowers Turn Yellow?

1. Soil pH

Gardenia loves acidic to slightly acidic soil to thrive and bloom and the optimum pH range is 5-6.5. If the gardenia’s soil doesn’t remain in the optimum range, then the many required nutrients form an unavailable form for gardenia plants. 

As a result, the plant can’t take the required nutrients and blooms turn yellow so fast.


Measure the pH of your soil with a soil pH meter(our pick: Atree Soil pH Meter). If the pH is lower than the optimum range, add some garden lime(our pick: Jobe’s Organics Garden Lime) to increase soil pH and if the pH is higher than that range, add some soil acidifier(our pick: Jobe’s Organics Soil Acidifier)

2. Nutritional Deficiency

Lack of nutrients can cause the yellowing problems of gardenia flowers. If there is no issue with soil pH then nutrient deficiencies may be the reason for the problem.


Apply the gardenia fertilizer by following the label directions. For quick results, you can feed quick releases fertilizer(our pick: Miracle-Gro Water Soluble Fertilizer).

3.Over and Underwatering

Over and underwatering shows the same symptoms. Wilting, yellowing gardenia leaves, and flowers may be the sign of over and underwatering.

A moisture meter can help you to understand the plants that go through over or underwatering. Also, you can insert the stick or finger to feel the moisture.


Never apply too much water at a time. Apply less water to your gardenia more frequently. Stagnant water can rot the root of the gardenias.

Apply one inch water per week. This the rule of thumb of watering to the gardenia plant. For indoor potted gardenia, repot the gardenia with a pot that has good drainage and aeration.

4. Environmental Stress

The most possible reason for the yellow blooms of gardenia is environmental stress and environmental stress is the result of light and temperature effects on gardenias plants.

This is the reason that’s why indoor gardenia flowers turn yellow.


You should know, gardenias hate direct sunlight. They love filtered sunlight. They can grow well in filtered light under tree shade. So, plant them in direct sun can create many problems such as poor flower sets, yellow and brown colored flowers, etc.

So, to revive and protect the gardenia plants from environmental stress as well as yellow flowers. Plant the gardenia in shade or place them in the side of the window that faces south and west where they can get at least six hours of shaded sunlight.

What will happen if the plant is already outside in the direct sun? Add some organic mulch or create shade by plant another plant or park your car in front of the plants. Sound silly, right? But it works.

5. Insect, Pest, and Disease

Some insects, pests, and diseases can make your blooms yellow too quickly. If you notice any insect activities, then you can understand you should take some steps to get rid of insects from gardenia.

But how do you know the plant is affected by any disease? Remember, yellow flowers are the last sign of disease. You can also notice some other sign-on gardenia plants if the plants are affected by diseases such as yellow leaves, black spots, and rust.


Apply insecticide, neem seed oil, or insecticidal soapy water on the gardenia plants to get rid of insects, and also you can spray fungicide if you notice any signs of diseases. I can tell you to spray fungicide because most gardenia diseases are fungal diseases.

Here is the recommended insecticide and fungicide for your gardenias-

  1. Safer Brand 5110-6 Insect Killing Soap(Ready to Use)
  2. Southern Ag – Liquid Copper Fungicide


I told you the most possible causes that make the gardenia bloom yellow and the solution to the problems. Hope this article helped you to get the white beautiful blooms of gardenia.

If you know any other causes of yellow flowers of gardenia, then don’t hesitate to share it with us. Your experience also can help my audience.

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