11 Spots On Orchid Leaves: Symptoms, Causes, And Treatment

spots on orchid leaves

Leaves are an indicator of the health of a plant organism. Tissue destruction, puffiness, atrophy, and spots on orchid leaves occur as in all types of orchids. This is a sign of illness or improper care of a potted flower.

Let’s discuss how these spots on orchid leaves occur, how to identify any spot on leaves of orchids flower and what are treatment for these spots.

Spots On Orchid Leaves

The external manifestations of lesions depend on the conditions of the flower, and the structure of the leaf plates (thick, thin, fleshy, tough, with and without veins). The spots are flat and convex. They are very diverse in color, size, and shape.

There are many types of spots some are:

  • White Spots
  • Black Spots
  • Brown Spots
  • Yellow Spots
  • Transparent and light Spots
  • Dark
  • Wet

White Spots On Orchid Leaves

White Spots On Orchid Leaves

Plants living at low air temperatures have a few specks – they react to a cold window sill, a draft from a window. White spots on thin-leaved varieties with subsequent purple or red coloration are a sign of phyllostictosis and other infectious fungal infections. A whitish bloom on plates, and buds is a symptom of another disease – powdery mildew.

If your Orchid Leaves Cracking read the guide for a solution.

Black Spots On Orchid Leaves

Black Spots On Orchid Leaves

They arise due to maintenance errors, and the development of various bacterial rot, fungi, and pests.

Identify black spots on orchid leaves:

  • a scattering of small dots with the further formation of large depressed spots with a white or yellow ring inside – a fungal infection characteristic of phalaenopsis, vanda;
  • black dry with a white rim found in all types of orchids against the background of a fungus;
  • depressed, localized at the junction of the leaves with the stem. At first, it seems as if they are bubbling, then the defeat crumbles. A dry net formation remains, and the plate falls off. A sign of fusarium wilting in all varieties;
  • convex, variably annular, sometimes slimy to the touch (fungus);
  • small, numerous, dry, depressed. From dots to large oval, round, diamond-shaped formations. A sign of neglected black spot, phyllosticosis;
  • at the beginning of the disease, the formations are yellow, over time the middle is pressed in, and turns black. The effect of a yellow rim is created around it. Sign of a viral infection, Alternaria, stangosporosis.

Important! Black, dark brown plaques with a yellow rim are caused by a heat burn when the sheet is exposed to the hot air of heating devices. In some varieties of phalaenopsis, damage appears from the sun. Stains cannot be treated.

Bacterial Brown Spot On Orchids

Bacterial Brown Spot On Orchids

Orchids leaf turning brown is Sign of bacterial lesions, or fungus.

Identify a bacterial brown spot on orchids:

  • brown wet areas go from the base of the plate, along the lobar vein, with a clear distinction between healthy and diseased tissues. Over time, they fill the entire surface;
  • large, rounded sign of bacterial and fungal spotting. Most often it affects Cattleya, Phalaenopsis, less often Vanda;
  • red-brown with yellow border rust, fusarium spotting has settled on the plant;
  • light brown wet, gradually darkening – septoria. The plaques are slightly depressed, surrounded by a yellow halo;
  • with a yellow rim and a dried core (up to holes) a sign of a fungal infection.

Yellow Spots On Orchid Leaves: Fusarium Wilt

Yellow Spots On Orchid Leaves

The most common type. Formed against the background of a deficiency of potassium, iron, overheating, poor lighting, due to damage to the roots, and stress. There are pests and fungal infections.

Identify yellow spots on orchid leaves or Fusarium Wilt:

  • ring-shaped flat formations on a yellow background – a fungus that lives on stangopeans, bifrenaria;
  • ring-shaped, merge into circles, pressed in, darken – an infection characteristic of Cattleya;
  • oval, ring-shaped, diamond-shaped – fungus on dendrobiums;
  • dry, of various shapes, and sizes, quickly darken, are pressed in – the disease affects zygopetalum, Pescatori;
  • yellow spots, the leaf is half green, gradually turns yellow, falls off – a sign of fusarium wilting;
  • slight spotting until the plates completely dry out, the presence of tied threads of yellow, red, and black color is possible – the plant received a chemical burn;
  • light yellow spots, slightly pressed in, over time overgrowing with yellow-brown rot – bacterial damage;
  • small plaques – scaly infection;
  • large, spreading to the entire plate – a natural aging process. Typical for adults, lower leaves of phalaenopsis.

If you are facing a problem with Miltoniopsis and its leaves turning yellow here is the answer Why do Miltonia Orchid leaves turning yellow?.

Transparent Spots On Orchids Leaves

Transparent Spots On Orchids Leaves

Caused by burns and disease.

Identify Transparent Spots on orchids leaves:

  • light ring-shaped, double oval, diamond-shaped, tissues are not pressed in – virus;
  • rings, stripes formed by small rectangular plaques. During the year they turn black – a virus;
  • first yellow, then pressed in, turn white on old leaves, without affecting young growth – a virus;
  • depressed, dry, light, with a dark border a sign of phomopsis. At first, the spot is light, but after 2 weeks the plate becomes thinner, like papyrus. The edges turn black, the leaf dies to the end. Another reason is black spotting;
  • wet white, with light dots inside, sometimes with a dark halo – sunburn;
  • dry, light, at first the lesion is filled with moisture, after 20 hours it is pressed in, turns white – excessive contact with water (found on wands);
  • transparent, white roughness – burn;
  • the plates lightened, overgrown with red dots – flat, spider mites;
  • transparent sticky discharge – mealybug, aphids, bugs.

Dard Spots On Orchid Leaves

Dard Spots On Orchid Leaves 1

Dark plaques of various shapes, sizes, and localization indicate the presence of a viral, fungal, or bacterial infection. The second reason is sun/heat burn, a consequence of excessive lighting (here is a guide for you on Growing Phalaenopsis Orchids under Lights). The wide spread of spotting in the core indicates a long-term presence of the orchid in the water. The condition is aggravated by low lighting, low temperatures, and high humidity in the apartment.

Wet Spots On Orchid Leaves

Wet Spots On Orchid Leaves

Formations are often overgrown with bloom, characterized by a rapid color change.

Identify wet spots on orchid leaves:

  • wet vitreous – rot, bacteriosis;
  • quickly passing from leaf to leaf, turning yellow on days 2-4 – late blight;
  • gradually darken, pressed in, acquire a yellow color along the rim – septoria;
  • transparent, watery with a gray, easily washable bloom – gray rot;
  • yellowish-brown, with an irregular distribution, intricate ring-shaped pattern. Over time, they merge, shrink, and darken to an intense brown color – bacterial rot (Cattleya, oncidium, and epidendrum are susceptible);
  • transparent or with a yellowish-brown tint. Over time, they acquire a mushy structure and secrete a yellowish secret – a bacterial infection (this is how phalaenopsis is sick).

Anthrax On Orchid

anthrax on orchid

Not a particularly dangerous disease, however, if not treated in time, it can lead to the death of the orchid. At the very beginning of the course of the disease, its symptoms are similar to a sunburn. However, the affected area of ​​the leaf grows over time and occupies a large area.

In appearance, the spot is distinguished by a yellowish border.
The causative agent of the disease is a fungus that develops in a humid and warm environment. If the disease is started, it can lead to the death of the orchid. However, timely measures taken to eliminate the disease will save the life of the plant and restore immunity.

To cure an orchid, it is necessary to take a set of measures:

  1. Protect the flower from neighboring plants.
  2. Remove all affected leaves. It is important to remove the entire leaf, and not just part of it, since anthracnose may well appear later in the same part of the flower due to the presence of pest toxins in the healthy part.
  3. Treat the wounds of the plant with disinfectants – iodine, brilliant green or charcoal.
  4. Treat with fungicides.

Preparations for anthracnose: Fitosporin, Difenoconazole, Azoxystrobin, Metiram.

Sooty Fungus

The disease appears after the infection of pests aphids, scale insects, and others. As a result of their vital activity, they leave toxins in the soil or leaves that impair the process of photosynthesis. As a result, the plant weakens and becomes ill with soot fungus.

Treatment for this disease is long and takes place in two stages. First, you need to wash the flower every day for a week, then treat it with insecticidal agents to remove as many pests as possible.

Then cut off the damaged areas of the plant and treat with fungicidal preparations. Treatment is carried out twice with a rest period of no more than 10 days. After treatment, the orchid must be transplanted into a new substrate and a new pot.

Rust Spots On Orchid Leaves

The infection comes from the fungi Puccinia and Sphenospora. Their spores spread through the air and settle on the leaves. Only weakened plants can get sick. Signs of the disease are spots of a convex shape with a red bloom, inside of which there is a powder.

Over time, if the orchid is not treated, the spots take over the entire plant, and it begins to wither. For treatment it is necessary:

  • wash the affected areas with warm water;
  • dry the orchid;
  • remove rust from leaf surfaces;
  • treat with disinfectants.

Phytophthora In Orchid

Orchid disease is caused by the fungus Phytophtora, which reproduces by spores. It is an infectious disease and very dangerous. If timely measures are not taken to cure it, then the orchid will die in a few days. The disease can be determined by external signs – leaves or roots become covered with wet spots.

After a couple of days, they become yellow, watery, and fall off.

To save the plant, you need to react as quickly as possible, as soon as the first signs appear:

  1. cut off infected areas with additional healthy tissue, since it is quite possible that the disease has not yet manifested itself there, but toxins are already destroying a healthy shell;
  2. treat the cut sites with disinfectants;
  3. the entire flower must be treated with fungicidal agents.

What Causes Spots On Orchid Leaves?

What Causes Spots On Orchid Leaves

Spotting develops due to unfavorable environmental conditions (incorrect watering, lighting, temperature conditions), damage by fungi, bacteria, viruses, pests.

Excessive Hydration Is Cause Of Spots On Orchids Leaves

Prolonged contact with water is harmful to any orchid, but especially often it ruins the vanda. If you forget the soaked plant for a long time, and water it too intensively, the tissues will deteriorate. The strength of the lesion depends on the individual structure of the leaves. Adjust the irrigation mode, and carefully soak the pot in the basin. Some varieties tolerate 20 minutes of contact with liquid, while others take 40 minutes. (Read also Choosing Best Orchid Pots for Phalaenopsis growing and reporting).

Feature! Monitor the quality of the irrigation water. High rigidity and concentration of harmful impurities create a toxic mass. It damages the root, and goes into the stem, destroying everything in its path.

Drying Out Of The Plant

Rare watering is the other side of the coin, often found among beginners. In hot climates, moisture deficiency leads to tissue dehydration. Having received water, the orchid directs it to the most heated problem areas. The liquid accumulates and breaks the plate along the lobar vein. The solution is to adjust the irrigation regime.

Infection With Fungal Diseases

It spreads by air or through irrigation water. Pathogens enter the plant through the stem, leaves, root system, and peduncles. The defeat can go top-down or bottom-up.

Types of fungal infections:

  1. Phylostictosis (brown spot).
  2. Fungi caused by the pathogens Naevala pyrexia, and Curvularia eragrostidis.
  3. Cercosporosis.
  4. Fusarium wilting.
  5. Septoria.
  6. Alternaria (ring spot).
  7. Stangosporosis.

The source of diseased plants is imported from Asia (cattleyas, dendrobiums). The effectiveness of treatment depends on the degree of damage. The sooner the pathogen is found, the faster the orchid will be healthy.

Important! In addition to the fungus, bacteria and viruses attack the culture. Infections cause various spots, wet/dry rot, and bacteriosis.

Mealybug May Be Cause Of Spots On Orchids Leaves

It sucks out the juice, injecting toxic toxins instead. The flower weakens, slows down growth, and loses leaves. The first sign is sticky drops and a cottony white coating on both sides of the plates. Reason for appearance: violation of containment conditions. The main delicacy of the pest is overfed with nitrogen, weakened orchid with impaired metabolism.

Usually, the insect attacks the flower in winter. It dies from high temperatures, therefore, watering with a hot shower at t 40-52 ° C is shown. Preparations based on the Nim tree, and Fitoverm work well.

How To Treat Spots On Orchid Leaves?

If the cause of the leaf spot is improper care, adjusting the conditions of maintenance will quickly bring the plant back to a healthy appearance. When time is lost, bacteria, fungi, and viruses destroy the flower, then it’s time to take serious action.

Resuscitation Of Phalaenopsis

Action plan:

  1. The orchid has lost its leaves with a growing point, retaining only a stump with a root collar and rhizome – plant in a fresh substrate in a mini-greenhouse. No spraying, with moderate watering.
  2. Leaves are completely or partially lost, 2-3 roots remain, a stem with a growing point – plant in fresh soil, use spraying instead of water.
  3. The peduncle is preserved without a growth point, horses, and leaves – divide into segments 2-3 cm with a dormant bud. Place on a wet sphagnum surface.

Methods For Propagating Orchids From Aerial Roots and regular roots for proper growth.

Phalaenopsis Flower Treatment With Drugs

Action plan:

  1. Isolate the orchid, and rinse in warm water.
  2. Wipe the leaves dry with a tissue or cotton wool, especially around the stains, to remove plaque from the spores.
  3. Remove affected areas to healthy green tissue.
  4. Disinfect the cut with charcoal or brilliant green.
  5. Use a specific fungicide (Benomil).

How To Prevent Spots On Orchid Leaves?

To prevent an epidemic, the affected plant is isolated from others. The window on which it stood washes well. The old soil is thrown away. The pots are washed and disinfected with a chlorine-based cleaning agent.

Important! Always inspect the plant before purchasing and look for infected areas. Infected imported flowers often end up in stores.

prevent leaf spots:

  1. Temperature control inside the substrate. The plant should not be cooled to low temperatures or overheated.
  2. Correct watering. Excessive moisture is an excellent medium for the development of pathogens.
  3. Soil composition control. Eliminate too much foam or peat. The substrate changes the acidity, expels beneficial microorganisms. The share of synthetics, peat is 10-20% of the total volume of components.
  4. Correct feeding. Excess nitrogen and iron leads to soil salinity, weakening the flower’s immunity.

Compliance with these simple conditions will allow you to grow a beautiful, spectacular plant at home. It is only important to pay attention to the intricacies of crop care and take the necessary measures in time.


As the practice of orchid plant growers has shown, it is safe to say that there are practically no incurable diseases. The main point in order to prevent the death of the plant is to diagnose in time and begin complex treatment.

It depends on the speed of response and diagnosis of spots on orchid leaves whether the orchid survives or dies. Also, do not get carried away with a too frequent and varied top dressing of the soil, oversaturate the orchid with moisture too, and put it under the direct rays of the sun.

I am an avid plant enthusiast and horticulture aficionado with a deep passion for houseplants. With years of nurturing green companions, my expertise in caring for indoor foliage is well-rooted. Through my journey, I've cultivated insights into optimal plant care, propagation techniques, and creating vibrant indoor ecosystems. Join me as we explore the verdant world of houseplants together. Let's turn your living space into a thriving oasis of botanical beauty. Connect with me on admin@houseplantspro.com and Facebook and explore more at Houseplantspro. 🌿🪴

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