It’s unfortunate to watch the leaves of a gardenia turn yellow like that. One of its primary selling points is its glossy, dark green leaves, which, in addition to the attractiveness and aroma of its blossoms, are quite attractive. This yellowing might also be a warning sign that the plant’s health is declining. Let’s begin by defining exactly what a gardenia is and going through the ideal environmental settings for its growth before moving on to the potential reasons for this discolouration and the ways in which it may be remedied.
What Exactly is a Gardenia Flower?
There are several distinct varieties of gardenia. Nevertheless, most of the time when people talk about gardenias, they are referring to the common gardenia (Gardenia jasminoides). The name of the species indicates that it has caused people to think of the jasmine plant, even though it is not real jasmine (genus Jasminum). In point of fact, “cape jasmine” is an alternative popular name for this plant.
Gardenias are evergreen shrubs that have broad-leafed foliage. Outdoor cultivation is possible throughout the year in USDA planting zones 8 through 11. It is common practice to cultivate them in pots for use in patio landscaping during the warm summer months, and then to bring them indoors as houseplants in the fall and winter months to protect them from the freezing temperatures. At full maturity, a gardenia may reach a height of up to 8 feet and a width of between 5 and 6 feet.
Gardenias are renowned not just for their sumptuous, snowy-white flowers but also for the heady fragrance that they exude. Gardenia oil is a component in a variety of fragrances and may be found in many of them.
Growing Needs.
Gardenias do best when grown on soil with a combination of the following characteristics:
- A pH level in the soil is acidic.
- Good drainage
- Sufficient nutrients from compost, etc.
- Adequate (but not excessive) moisture
- Yellowing of the leaves may be an indication that one or more of these requirements for growth have not been met.
The Factors That Led to the Discoloration.
Even while you never want to see yellow leaves on your gardenias, it is essential to understand that the appearance of these leaves does not necessarily imply that there is an issue. It’s not uncommon for some of the leaves to turn yellow when spring arrives. This is a natural occurrence that occurs as an older generation of leaves falls off to make space for the next generation of leaves.
It is not typical for gardenias to have a significant amount of yellow leaves during other times of the year. The fact that you cannot easily ascribe the yellowing to a single source is one of the things that makes the situation more complicated. Instead, you will need to work your way through a list of potential reasons in order to get to the bottom of the issue. When analyzing a specific gardenia that has a problem with its leaves becoming yellow, you must begin by eliminating all of the probable explanations that do not fit before moving on to the one that does.
You should begin by looking for telltale indicators of sickness (such mold that fungus have left behind) and insect infestations so that you can eliminate these possibilities (or treat them immediately if they are present). After you have determined that your gardenia is free of illnesses and insects, you should investigate the potential that it has chlorosis.
Chlorosis
It is often gratifying to be able to give a name to a problem; nevertheless, stating that a plant with yellow leaves has chlorosis is actually merely scratching the surface of the situation.
To speak in terms that are more precise, it indicates that the plant in question is not receiving an adequate amount of chlorophyll and is consequently suffering from a nutritional deficit.
However, this does not in any way pinpoint the root of the problem from a practical standpoint. A shortfall of this kind may have more than one cause at any one time. In addition, there are a variety of distinct forms of chlorosis (each indicative of a different nutrient deficiency).
Send a sample of the soil you want to test to the county extension office in your area, and ask them to check it for any deficiencies. When the extension delivers the findings of the test to you, it may also provide a recommendation for a solution.
Finding a Solution to the Problem
However, you shouldn’t automatically think that applying fertilizer would address the issue by itself. The problem may be that the gardenia is unable to reach the needed nutrients in the soil, despite the fact that such nutrients are available in the soil. Because of this, it is essential to have a good understanding of the ideal pH level for the soil your plant should grow in. Though acid-loving plants like gardenias are grown in soil that is excessively alkaline, the essential nutrients such plants require will not be accessible to them, even if the soil itself has those minerals. Utilizing a fertilizer that contains sulfur, for instance, is one way to bring the pH level of the soil down and make it more acidic.
The problem of nutrients being unavailable can also arise if the plant in question has suffered root damage. This is something that can happen if the roots of your gardenia are allowed to stay in water for an extended period of time. Roots have a respiratory system, and submerging them in water prevents them from receiving oxygen, which can be harmful to the plant. Because of this, it is essential to pay attention to two of the other requirements for growing gardenias, namely, soil that has appropriate (but not excessive) moisture and good drainage. These characteristics are closely connected to one another due to the fact that soil that has poor drainage is likely to be overly moist even if the gardener does not over-water the plants.
If there has been root damage, it is possible that the problem can no longer be fixed (and it would be a lot of labor to do so): replace the gardenia. Just said, you shouldn’t repeat the error that you made the first time, whether it was excessive watering on your part or simply inadequate drainage. When you water, you want to achieve a consistent level of moistness throughout the root zone of the soil; yet, it should not be waterlogged. In order to avoid issues with drainage, it is important to incorporate a great deal of organic matter into the soil.
Fertilizing.
Consider yourself fortunate if you have been able to determine that the yellowing of the leaves on your gardenia is not the result of an improper soil pH, inadequate drainage, or excessive watering. The fourth requirement for growth, having sufficient nutrients, is not difficult to fulfill if there has been a deficiency in this area. It’s as simple as fertilizing. To begin, apply a fertilizer that is well-balanced unless you are absolutely certain which nutrient is deficient. If this is the case, you may refine your approach by applying a fertilizer that is rich in deficient nutrients. Take special care to carefully adhere to the application directions.
