For inexperienced flower growers who decide to grow exotic plants at home, sometimes they simply give up due to excessive care associated with ignorance of the biological and physiological characteristics of orchids if The orchid begins to rot before our eyes.
it is difficult and problematic to grow such a plant at home
It turns out that everything is not so difficult if you try to understand the causes of decay and know what to do to revive the tropical beauty.
Orchids, although capricious to care for, are quite life-loving and can almost always be resuscitated.
Why does orchid rot?
Putrefactive processes in any part of the plant are mainly associated with increased and prolonged humidity at low ambient temperatures . This is especially true for inexperienced flower growers.
Having no experience, not knowing the physiological characteristics of tropical orchids, they care for their pets too hard, not realizing that they are only harming the plant.
Causes
The main reasons why an orchid rots when grown at home are:
- excessive watering;
- poor quality soil;
- Greenhouse effect;
- sunburn;
- hypothermia;
- organic fertilizers;
- excess fertilizer;
- weakened plant;
- pests
Often the cause of rotting is excessive watering.
Which plant organs are under attack?
The most vulnerable part to putrefactive processes is the root system . Overwatering causes the soil to become compacted and decompose, and in the absence of good ventilation, rapidly spreading pockets of rot are formed.
Second place belongs to the leaves of the plant . Damage by direct rays of the sun or pests opens the flow of air into the intercellular tissues, where the process of decay begins.
The third place belongs to the pith or stem . Inaccurate watering, irrigation or pests quickly lead this part to the center of the spread of the fungus.
Symptoms of root system diseases
Since the orchid is an exotic flower, in unusual conditions it often develops a tendency to disease. And often problems of the root system are rotting or drying of the roots. They rot mainly due to improper moisture: as a result of excessive watering, the moisture does not have time to be absorbed and is retained in the pot. If the roots turn black, this means that they are disappearing and must be urgently pruned.
Under natural conditions, orchids grow in an environment where changes in humidity are quite frequent, so during evolution they have developed enough ways to protect themselves from drying out. Therefore, constant hydration is unnecessary. In addition, periods without watering activate the formation of flower stalks. During the dormant period, the plant also needs to reduce moisture intake.
The roots become dry in two cases:
- lack of moisture;
- burns from fertilizers due to too much saturation or incorrect selection.
For the first problem, the roots need to be rinsed in water at room temperature and well moistened. In case of burns, the orchid must be transplanted into another soil, less aggressive. The affected parts that cannot be resuscitated are necessarily removed in both cases. Finding out which roots to cut is quite simple.
- Rotten ones are yellowish-brown in color, slippery and too flexible. This indicates that they are empty inside, only the shell remains, and they can no longer be restored. Be sure to cut them above the affected area.
- Shrunken ones also become yellow, hard and brittle. They should not be broken off so as not to damage the stems. You need to cut it with a knife or pruning shears and treat the cuts with crushed charcoal.
The yellow or brown color of the roots does not always indicate disease. In some cases, they change color due to lack of sunlight or substances they absorb from the substrate.
If the root system is overdried, the turgor of the leaves, that is, their normal state, can be restored by soaking the roots. The orchid is removed from the substrate, the roots are washed, dipped in a container with water at 30–35°C and left for some time (no more than 6 hours). You can carry out this procedure for several days in a row, but then the time spent in water should not exceed 2 hours. Foliar feeding will also help to restore turgor, which is used in the case of severely damaged roots or in case of urgent need to restore the trunk. Liquid nutrients are applied to the surface of the leaves, thereby promoting their renewal.
It happens that the leaves and roots of the flower become covered with a white coating. This is how mold, a fungal disease of plants, manifests itself. It appears from excessive moisture or elevated temperature in the room, as well as when purchasing an already infected flower in a store. Quite often, the roots of a seemingly healthy plant become covered with white dots or balls. The appearance of whitish spots of different sizes may be due to water hardness. Salts deposited in the soil do not allow air to flow normally into the cells of the root system; this is manifested by white dots on the roots and in the substrate. Small balls are the mycelium of soil fungi; this form serves as a protective barrier from adverse external influences. When a suitable environment is formed, they grow and cover plant roots and soil with a web, taking nutrients from it.
If measures are not taken against the spread of fungi, the roots of the plant will die over time. Also, due to unsatisfactory maintenance conditions, the roots of the orchid may turn white. In such cases, the plant is replanted and all the rules of necessary care are subsequently followed.
Types of rot
Gray
A fungal disease caused by the fungus Botrytis cinerea. Ideal conditions for formation are a cold, damp atmosphere with poor air ventilation . Initial appearance on flowers in the form of small brown spots .
As the spots progress, they enlarge and are framed by a pale pink halo . The final phase of spread is the merging of the spots into one and the appearance of gray membranous sprouts (mycelium) of the fungus.
Gray rot on orchids (photo of the back of the affected leaf).
Gray rot on the petals.
Under ideal conditions, an infected plant is capable of releasing spores into the environment. At temperatures from 18 to 23 ° C and humidity of at least 90%, the spread of infection to healthy tissue occurs quite quickly - within 12-15 hours. The most susceptible to the fungus are Phalaenopsis and Cattleya.
Attention! In 90% of cases, a weakened plant is affected.
Brown or bacterial rot
The causative agents are bacteria of the Erwinia, Pseudomonas and others families. Young leaves and shoots are most often affected . Lesions appear as wet brown spots that cover the entire area of the plant before our eyes. If a stem or growing point is affected by brown rot, it dies.
The action of bacteria progresses if the humidity is above 60% and the ambient temperature is 15° and below.
Susceptible to this type of rot:
- Phalaenopsis;
- Cattleya;
- Cymbidium;
- Paphiopedilum.
Bacterial rot.
Another photo of the bakt. rotten.
If the damage is severe, the plants are destroyed. Local, small lesions are cut down to living tissue, and the section is disinfected with crushed activated carbon. Conditions and care are improving.
For preventive purposes, under favorable conditions for the spread of bacteria, spraying is carried out with preparations based on copper.
Black
The causative agents of this fungal disease are soil-dwelling Pitium fungi, which lead a parasitic lifestyle.
And although the main damage occurs to young roots, since they are not yet protected by a reliable coating, when it spreads, it affects all parts of the exotic plant, regardless of age.
The greatest danger is the formation of foci of rot on the root system and at the bases of tuberidia. The danger lies in the rapid spread of lesions to healthy areas. The roots quickly turn black due to tissue necrosis, and the tuberidia become mummified.
The conditions for the spread of black rot are low temperature and high humidity of the environment and soil . Under such conditions, the underground part develops slowly. Some roots do not have enough air in the moisture-saturated soil, and they gradually die off, which makes it easy for pathogenic fungi to penetrate them.
The most accessible black rot are the following types of orchids:
- Cattleyas;
- stangopei;
- laelia;
- leliocattleya;
- paphiopedilum, etc.
Even at normal temperature and humidity, mushrooms do not die . The spread processes slow down and proceed much more slowly. Extensive activation of putrefactive processes leads to the death of the tropical beauty.
Black rot.
You can save the plant in the initial stages of damage . Since development occurs in patches, optimizing moisture and treating with copper-containing preparations will not only significantly slow down the process, but in the early stages can cure ocher.
Dry rot
On orchids, according to some sources, dry rot is nothing more than fusarium. But there is another concept of dry rot - this is southern sclerotial rot.
Southern sclerotial
An infectious disease caused by the fungus Sclerotium rolfsii. It appears on almost all parts , but especially on the roots and stem, and at the same time.
Soil-dwelling fungi that can remain viable for many years. The infection occurs not only with low-quality soil components, but also with irrigation water.
Ideal conditions for propagation are considered to be a temperature of 27-33° C and high humidity.
Southern sclerotial rot.
More photos.
Important! At low humidity, the disease multiplies just as quickly, differing only in a different development process.
If wet rot is in many ways similar to various types of root rot, then dry rot mainly affects orchids growing on blocks.
Fusarium
A fungal disease caused by the fungus Fusarium moniliforme var. Lactis. Spotting on yellowed leaves and their curling is the main symptom of fusarium. The tissues of the leaf blade lose their structure, soften and become covered with a whitish-pink coating formed by fungal spores.
The orchid quickly takes on a dull gray appearance. The central shoot rots and subsequently dies.
Fusarium.
Fighting the disease is quite difficult and takes a long time. For 7-10 days, it is subject to treatment with the drug foundationazol several times a day .
Reasons for these processes
Rot of living plants can be caused by many factors, we want to show you some of them.
Pathogenic mushrooms
- Cylindrocladium, Rhizoctonia - affects leaves, causing rot and drying out of the plant.
- Fusarium oxysporum - causes rot of stems, roots, wilting of leaves and flowers.
- Pythium - causes rotting of the neck, followed by yellowing and falling off of the leaf.
- Phytophthora - gradually increasing spots of wet rot on leaves.
Fusarium also often causes rotting. You can read about this disease here.
Bacteria
Pectobacterium, Erwinia, Cattleya, Epidendrum, Oncidium - cause wet bacterial rot, which causes tissue decay. The fleshy parts of the plant are mainly affected. The process begins with a small spot on the leaf, brown or gray in color, which gradually grows. Often it is the cause of rotting of the core; less often, bacteria first infect the root or peduncle.
Viruses
It is worth noting that the manifestations of orchid viruses are similar to each other, therefore, to clarify the causative agent of the disease, it is necessary to conduct laboratory tests.
- Orchid fleck virus, Odontoglossum ringspot virus, Dendrobium mosaic virus are viruses that slowly infect leaves and are difficult to distinguish from each other. It can look different on different types of orchids, but what remains common is that double various figures gradually appear on the leaves, built from spots of different shapes.
- Tobacco Mosaic Virus is an aggressive virus that most often occurs together with other viruses. Affects flowers: under its influence they become covered with multi-colored spots, look rotten and become deformed.
- Phalaenopsis chlorosis spot virus is a virus that destroys chloroplasts, as a result of which yellow spots first appear on the leaf, the surface of the leaf is pressed in, the spots gradually become white, then dry out completely.
- Cymbidium mosaic virus - gradually growing, sometimes depressed yellow (or white) spots on the bottom of the leaves. Does not cause deformation. – Turnip mosaic virus – small spherical swellings appear on the orchid.
Important! Some viruses are endemic only to certain varieties of orchids, while others are common to all. They may appear differently on different varieties of flowers.
Improper care
- Waterlogging of the soil.
- Low water temperature for irrigation.
- Low room temperature.
- Poor lighting in the room where the flowers are located.
- Excessive use of various nitrogen-containing fertilizers.
- Poor indoor air circulation.
All these factors, taken together or individually, lead to plants becoming sick, and diseased plants often have to be destroyed to avoid infecting other plants.
Course of the disease
Different species of orchids are affected by pathogenic fungi and parasites in different ways and under different conditions. Also, the clinical picture looks different.
Pathogenic fungi enter plant tissue due to the presence of certain enzymes. Having penetrated inside, toxins are released, which provoke the formation of rot that decomposes the fabric.
Any, even minor, damage to the roots, leaves or stem allows air to enter the wound and, accordingly, the development of pathogens. Oversaturation with moisture leads to tissue destruction, which is the main culprit in the development of fungal diseases.
Terms of distribution
Fungal diseases, caused by various types of fungi, develop and spread under certain conditions . But, basically, the conditions are related to temperature, humidity and lighting.
Some types of fungi, such as Phytophtora cactorum, require high humidity and temperature, while others require dry air and low temperature.
Therefore, it is advisable for flower growers to know the physiological and biological characteristics and characteristics of the type of orchids grown at home.
It is proper care, the creation of the necessary conditions, the absence of “excessive” care and the implementation of the recommendations of experienced orchids that will ensure the health of exotic beauties.
External signs of damage
Rot is the process of decomposition or destruction of intercellular substances, tissue cell walls and the entire contents of a plant cell. Such pathological processes are caused by semi-parasitic and saprophytic fungi or bacteria. The process of tissue breakdown into cells occurs, which weaken and cease to function, as a result of which the work of tissues and organs stops.
External signs of putrefactive processes, both aboveground and underground, may differ depending on the type of fungus, but, one way or another, they form initial, local foci of damage:
- the appearance on young leaves and shoots of watery light brown spots, quickly darkening and increasing in size until merging into one continuous spot;
- brown and black spots covered with a terry gray coating;
- dark brown shades on roots and leaves;
- yellowness, darkening, the appearance of oozing ulcers on the leaf blades;
- brown spots on flowers;
- blackening of the root system.
Blackening of the roots may be a sign of rotting.
Attention! Bacterial infections occur much less frequently than fungal infections. If pathogenic fungi attack under certain conditions and in weakened places, then bacteria attack when the plant is completely weakened.
Unpleasant natural process
Rotting is the process of bacterial decomposition of protein substances occurring due to putrefactive microflora. The biochemical composition of tissues changes, cells lose connection with each other, since the intercellular substance is destroyed, the entire tissue becomes loose and loose. With high humidity and high temperature, the process accelerates. Decaying tissues become brown or black, soften, and acquire an unpleasant, specific odor.
All indoor plants are susceptible to infection, including fragile and vulnerable orchids, especially those who are not yet accustomed to caring for them properly. Improper care can provoke the awakening of putrefactive microorganisms.
Consequences
A rotten orchid very quickly loses its immunity and weakens . A weak plant is unable to resist the disease, and leaves with areas of rotting cease to participate in photosynthesis. When the roots become putrefactive, the above-ground part stops receiving nutrition and gradually dries out. Small local outbreaks do not pose a threat if they are eliminated in a timely manner.
General state:
- oppression and weakness of the orchi;
- loss of turgor in the leaf apparatus;
- reduction or loss of plant decorativeness;
- reduction in flowering duration;
- inhibition of photosynthesis processes;
- slowness or complete stop in growth and development.
The main signs, one way or another, are associated with the appearance of any spots on the leaves, stems or flowers. The florist should be concerned about their appearance and find out the reason . Otherwise, pathogenic fungi or bacteria will cover not only the plant itself, but also those adjacent to it.
With root rot, the above-ground part can remain seemingly quite healthy for a long time. But the process of rotting of the root part will make itself felt over time. The consequences can be quite dire. If timely measures are not taken, the plant will die quite quickly.
What do rotten roots look like?
Healthy orchid roots are whitish-gray in color, and immediately after watering they acquire a greenish tint. Any deviation from the norm indicates a problem with the root system.
Rotten roots become soft, watery, the top layer is easily separated, exposing the central thread. The outer layer of fabric is brownish or brownish-black. Blackened and dried out tips of an otherwise healthy root indicate a burn resulting from a high dosage of fertilizer.
The roots dry out as a result of damage to southern sclerotial, or dry rot, which is more often observed on monopodial orchids, for example, vanda or phalaenopsis.
What to do and how to save an orchid if it is rotting:
Here we will take a closer look at what to do if the orchid is rotten. It should be borne in mind that rescue measures will vary depending on the affected plant organ.
Trunk?
If an orchid's trunk rots, this is one of the most dangerous processes for its life . If the outbreak is too large and has captured most of it, then it is almost impossible to save such an orhu.
If a large area of the trunk rots, the orchid cannot be saved.
There can be many reasons for trunk damage , ranging from frostbite to mechanical damage. Black spots may appear on the trunk or it may begin to turn yellow. It all depends on the cause and type of disease.
In any case, timely detection of a defect on the stem increases the chances of saving the tropical beauty by an order of magnitude.
Standard resuscitation methods:
- removal of foci of rotting to healthy tissue;
- processing of sections;
- transplantation and special care.
Monopodial orchids have one short trunk, on which all the important parts of the plant are located: roots, leaves and growing point. For this reason, it should be given increased attention. Therefore, if an orchid rots at the base, this is a very alarming sign.
Core?
Rotting of the core (growing point) is a rather rare but common phenomenon. This usually occurs as a result of some kind of infection, rather than from the process of rotting caused by stagnation of water. For the core to rot, water must remain there for at least a day.
In an apartment (it’s hot in summer and heating in winter), this is almost impossible; it will simply evaporate. But, if a tropical monopodial beauty stands under the sun's rays, then the sun can burn the tissue or quickly evaporate moisture, which will lead to a sharp cooling of young leaves.
Such a sharp drop is similar to frostbite, as a result of which the young leaf plate becomes damaged and, accordingly, open access to pathogenic microorganisms.
A completely different picture is observed in the autumn-winter period, when the heating is not yet working and the room is cool. Water cannot evaporate for a long time; it stagnates. Tissue destruction depends on the condition and tenderness of the leaf blades of young leaves. The more tender they are, the faster the destruction of their tissues will begin.
First of all, it is necessary to strictly follow the rules of plant care and hygiene.
Preventive actions are based on the following requirements:
- lighting, temperature and humidity are three parameters that determine location;
- watering is carried out only when the substrate is completely dry;
- regular ventilation ;
- removing water accumulated after watering from the core using a paper napkin for 30-40 minutes.
To avoid rot, always remove water from the leaf axils.
To avoid the spread of rot deep into the trunk and onto adjacent leaves, the source of damage is cut out to an area of healthy tissue . And the cut areas are disinfected and dried. During the first few days, you need to monitor the cutting sites. The appearance of new signs indicates that the cut size is insufficient.
Important! If the core is completely rotten, then you should not be afraid of cutting it out completely. Without it, the orchid can be revived. If the putrefactive process spreads throughout the ocher, there will be nothing to reanimate.
The top?
Why does the top of the orchi suffer and rot? There are two main reasons: infection or errors in care.
If any rot affects the top, it must be cut off . The cut site is cleaned, treated with a fungicide or disinfected.
Further care for the remaining stump is standard, as for a regular orchid, with the exception of spraying and additional nutrition. With proper care, a baby will emerge from this stump in 50-60 days. The active growth of the baby allows feeding with a balanced diet.
Growth point?
No matter how resilient an orchid is famous, if the growing point rots, the chances of saving it are estimated by experienced orchidists to be 50 to 50.
It is important to prevent infection from spreading throughout the entire stem and root part.
Even in the absence of a growth point, a monopodial orchid will be able to live, since it will be able to reproduce with the help of children.
Bulba?
Rot in any part of the plant should alert the gardener. Bulba is no exception. Rotting of the base of the bulb is especially dangerous, since the infection spreads quite quickly and can cause damage to the root system. Then only a miracle can save the exotic.
The rescue process is standard - “surgical” intervention. The putrefactive focus (or the entire bulb) is removed down to living tissue , disinfected, dried, and watering and fertilizing are stopped for a while.
What to do to prevent foliage from disappearing?
If a gardener notices that the leaves of a plant are beginning to rot, measures should be taken immediately to save it:
- Place the flower in another room to isolate it from healthy plants.
- Trim off any damaged leaves. In this case, the instruments must be calcined or treated with an antiseptic. The resulting cut on the trunk is also disinfected using activated carbon or an alcohol-free antiseptic.
- After removing the damaged leaf part, a fungicide is applied.
- Be sure to treat the window frame and the window sill on which the diseased orchid stood.
- If possible, the flower is transplanted into another flowerpot, and the old one is soaked for four hours in a soap solution.
- After treatment, it is recommended not to moisten the soil for a week.
- Be sure to inspect the resulting wounds at the moment insects appear in them and treat them every day with charcoal, cinnamon or an antiseptic, but only without alcohol.
Attention! To avoid rot getting into the core of the flower, all leaves should be trimmed to the green tissue. If there is rot inside the core, it should be removed, the plant will be able to live without it, it will just take a little longer to recover.
Drugs for treatment
In this section we will look at how to treat an orchid from rot.
Fitosporin
The basis of microbiological Fitosporin, effective in the fight against fungi and bacteria, is the natural bacterial culture of Bacillus subtilis. Systemic work, the ability to spread through blood vessels, allows it to successfully suppress infectious agents.
The effectiveness against a wide range of fungal and bacterial diseases is caused by the presence of humate in the composition of various fillers and OD, which enhances the fungicidal effects and stabilizes the characteristics for a long time. Due to these characteristics, the shelf life is about 2 years, and shelf life is not limited.
Fitosporin.
The main use of Fitosporin is preventive treatment . For diseases in a serious stage it is ineffective.
The use and administration of the drug is carried out strictly according to the instructions . In orchids it is used to treat the soil and root part before planting.
Has a low danger rating and does not pose a threat . Upon contact, it sometimes causes irritation to the mucous membranes, so basic hygiene is required.
Quadris
Systemic fungicide from the group of strobilurins and the active substance Azoxystrobin. It is in demand as a preventive and therapeutic agent.
The high hazard class warns gardeners about careful use for indoor plants. Protects after treatment for about 2 weeks.
Foliar spraying is effective for treating fungi and bacteria.
Quadris.
Copper sulfate
Acts as a fungicide and antiseptic . The main active ingredient is copper sulfate, the ions of which react to the enzyme complexes of fungal or bacterial cells and, thereby, cause irreversible changes.
In addition to treating diseases, copper is a foliar feeding . Antiseptic properties help disinfect the substrate and flower container.
It is used both for soil treatment and for spraying. Concentration is carried out strictly according to the instructions for decorative indoor plants.
Hazard class 3 can cause severe irritation to the mucous membranes in humans, so treatment requires gloves and goggles. Follow all hygiene rules.
Bordeaux mixture
It is one of the most powerful remedies against fungal and bacterial infections. It is made using special proportions of quicklime and copper sulfate (copper sulfate and calcium oxide).
Copper sulfate acts as a poison against fungi and bacteria, and calcium oxide acts as an oxidizing agent neutralizer and prevents burns on plants.
Bordeaux mixture is one of the most aggressive means of fighting infections.
Important! Experienced flower growers do not recommend using Bordeaux mixture for treating orchids , since the delicate parts of the plant can be easily burned with the product. It is better to use drugs that do not contain copper.
Mikosan
A biological product whose action is aimed at increasing the resistance of plants to fungal pathogens . It stimulates the production of lectins in tissues, which disrupt the growth and development of fungi and bacteria. Mikosan does not kill the disease , but stimulates the plant to fight it.
The product can be used only at the initial stage of the disease, when the first spots and spots appear on the leaves. Even suspicious stains can be treated.
Attention! It is pointless to treat massive areas of rot or affected leaves with Mikosan.
Biological product of hazard class 4. Simple hygiene rules are required.
Alirin
A biofungicide that suppresses fungal infections in the substrate and on the orchid . The active bacteria are Bacillus subtilis.
When used, triple treatment is required, with an interval of 7 days. Compatible with growth stimulants and insecticides.
Hazard class 4.
Traditional methods of disposal
In general, only strong chemicals can cope with fungal or bacterial infections. Traditional methods can help if the focus of decay is insignificant and identified at the very initial stage.
Iodine solution
Use as a spray at the rate of: 5 drops of iodine per 5 liters of warm water.
Garlic tincture
Garlic peel in an amount of 100 g is infused in a bucket of water for 20-24 hours . The plant is treated with the prepared, strained solution.
To prepare garlic tincture, only the husk is used.
Mustard infusion
Take 50 g of dry mustard and infuse 5 liters of hot water for 48 hours in a dark, warm place. Before processing, the masterbatch is diluted with water in a 1:1 ratio.
Important! Traditional recipes are not harmful, not toxic, but even with the slightest development of fungal or bacterial infections, they are practically ineffective. You can’t do without chemicals in the fight against rot.
Folk remedies have performed well as preventive drugs.
Prevention measures
A rotting orchid is a sad sight. To avoid encountering it, prevention should be carried out.
Effective preventive measures accumulated by the experience of orchid growers:
- comfortable temperature with differences of no more than 5° C;
- humidity 50-60%;
- moderate watering, allowing the substrate to dry out;
- removing water from the leaf axils;
- diffused and sufficient lighting;
- ventilation, avoiding drafts and cold air;
- strict adherence to the rules and concentrations of fertilizing.
Flower growers who decide to grow an exotic plant at home need to remember that a healthy, strong plant with good immunity is practically not susceptible to any kind of disease. Therefore, proper care and maintenance of the required growing conditions is the key to strong immunity and, accordingly, a healthy plant.
