Diseases and pests of phalaenopsis orchids: methods for their treatment and elimination
Blooming phalaenopsis orchids adorn many florist apartments, and any of them will be upset if the flowers begin to hurt. In this article, we will consider what diseases and pests are affected by these orchids and in what ways to deal with similar problems.
Basic rules for growing orchids
Orchids will be healthy and blooming if you follow the rules for caring for them, which consist in observing the following factors:
- Temperature In summer, the temperature for growing phalaenopsis should vary between +25 ... + 28 ° C, and in winter should not be lower than +15 ... + 18 ° C.
- Lighting Orchids need a lot of sunlight, but it should be diffused - the flower pot is best placed on the eastern windowsill. If it stands elsewhere, make sure that the flowers and leaves of the orchid are in the correct color. In the warm season, the pot can be taken out to the balcony or terrace, making sure that the plant is not exposed to direct sunlight, which these sensitive flowers are afraid of.
Did you know? Orchids form numerous and very small seeds that can germinate only in symbiosis with mushrooms. Because of their size, the seeds lack nutrient tissue, and therefore they can germinate only if they are infected with a fungus.
- Moisturizing . These orchids do not tolerate wet soil - you need to water the flowers only when all the soil in the pot becomes dry. This can be checked by the weight of the pot: a pot with dry soil will be light, clicking on it will ring back. A container with wet soil will weigh significantly more. Depending on the indoor conditions, the soil in the pot may dry within 10-12 days.
In case of excessive watering, the root system of the plant is threatened with decay. Water should not be too cold - its most optimal temperature will be room temperature. When orchids fall into a dormant period, watering is significantly reduced (up to two to three minimum waterings per month).
- Humidity . For the normal health of flowers in a residential building, air humidity should be maintained within 40-50%.
- Watering time . Orchids are watered in the morning: the soil substrate will dry out before evening, which will prevent the occurrence of diseases associated with the effect of low temperatures on the wet parts of the flower. After abundant watering, pour water that drains from the pot into the pan. The best water for irrigation of tropical beauties is distilled, but you can also use boiled or settled tap water. In areas where there is no industrial pollution, the orchid can be moistened with rainwater, which she will like very much.
- Fertilizer . These plants do not need frequent top dressing, just one, a maximum of two top dressings per month, preferably a special fertilizer for orchids, is enough.
- Substrate . As a soil for growing orchids, a mixture of tree bark, coconut fiber, pine nut husks and perlite is used. Such soil is permeable to moisture and air. At the bottom of the landing tank should be drainage that does not allow the roots to rot.
Read also what the composition should be and how to make the soil for orchids with your own hands.
Phalaenopsis diseases and methods of their treatment
With improper care, orchids can get sick: stop growing, lose leaf elasticity, drop flowers, and more. Also, these flowers can be exposed to diseases caused by fungi, bacteria or viruses.
Fungi infect any part of the phalaenopsis. At the first signs of infection, the orchid can be treated with biological agents, such as Fitosporin-M, Trichodermin. In severe cases, only chemicals are effective.
The most common fungal diseases of orchids:
- Fusarium One of the first signs of Fusarium rot is the yellowing of the lowest (oldest) leaves. At the junctions of the petioles with the stem, black rot with an admixture of red blotches is visible. A flower infected with Fusarium should be burned. It is recommended to treat the flowers growing next to the patient with phalaenopsis with the drug “Topin” (outside the living room!).
- Anthracnose . The disease also affects the leaves of the orchid, after which black spots appear on them. Spotted leaves must be cut off and burned, and the flower should be sprayed with preparations containing copper (copper sulfate, Bordeaux mixture).
- Gray mold . The disease develops rapidly in cold temperatures and high humidity. Mushroom spores are carried through the air. Symptoms of gray mold appear as gray, watery spots on flower petals. With the development of the disease, the plant is completely covered with gray moldy coating. For the prevention of this disease requires constant air circulation and forced ventilation of the room. Peduncles infected with gray mold need to be cut. To treat a diseased plant, fungicides are used ("Quadris", "Alirin", Bordeaux mixture, "Mikosan").
- Powdery Mildew The first sign of the disease is leaves powdered with white plaque. Ill flowers are treated with a solution of colloidal sulfur. If this disease manifests itself, urgent measures must be taken, otherwise the flower will die within 7-10 days.
- Black rot . The root system is sick, spores of the fungus carry insect pests (aphids, mealybugs). Pathogens develop with high humidity in the room and an excess of nitrogen in the soil. The main sign that the plant is infected with black rot is a white-pink coating on the surface of the leaves.
- Late blight . The underside of the leaf plate turns light green, and brown or black spots are visible on the top. It is necessary to remove the infected parts of the plants, and then spray the flowers with a fungicide, for example, the drug Fongarid.
Usually viral infections are transmitted from one plant to another. Most often they are spread with the help of infected tools (knife, scissors), so it is necessary to disinfect them before starting work with the next flower.
Other methods of transmitting viruses from one plant to another:
- sucking pests (aphids);
- reuse of water passing through the substrate in which the infected plant grows.
Unfortunately, there are no cures for viral diseases of orchids, so infected plants must be completely isolated from healthy flowers or destroyed. Viral diseases often occur covertly over long periods of time and occur only when the plant is stressed. The most effective method of combating viruses will be the timely destruction of pests.
Important! When destroying a diseased orchid, you cannot put it in a compost heap, as the virus will survive and eventually pass to other plants. Signs of viral infections:
- Elongated stripes appear on the leaves or pseudobulbs - at the beginning of the appearance, the stripes look like yellowish lines, but soon change color to black.
- Round annular spots appear on the flower - the developing dark rings with a blurry pattern inside are clearly visible on the leaves.
- There are colored stripes on the flower petals - this may turn out to be a mosaic virus. You must make sure that the correct conditions for growing phalaenopsis are observed. If the problem persists after three blooms, then most likely it is a viral problem for which there is no cure. The mosaic virus can pass from any infected plants (not orchids) through insects or tools.
Video: all about orchid diseases and their treatment
Of all the diseases caused by bacteria, phalaenopsis is the most susceptible to wet bacterial rot . The infected leaves soften, acquire a watery consistency and smell bad. You can try to stop bacterial diseases (at the beginning of development) by cutting off sick leaves and dusting sections with ash. It is most reasonable to remove a plant infected with a severe form of wet bacterial rot from the house so that neighboring flowers do not become infected.
Another possible disease is bacterial spotting . Symptoms are the appearance of small wet spots on the leaves, yellowing and darkening of individual leaves. Over time, the disease develops, and changes in the color of the leaves become more intense. On the underside of the leaf plate are gray clusters of bacteria.
Bacterial diseases are treated by treating plants with fungicides. There are no special fungicides for orchids, they are suitable for the same drugs that are used to treat any vegetables or flowers.
Problems with orchids arise due to improper care and inappropriate growing conditions. In homes and apartments, the cause of problems is too dry air.
Orchids grow well in the heat, combined with a high moisture content in the air, which is impossible to achieve at home. To satisfy the plant’s desire for moisture, it is sprayed daily with water on a leaf or an automatic humidifier is placed next to orchids. Orchids also react negatively to waterlogging, the introduction of large doses of fertilizing, frequent transplantation and low temperatures. The result of excess feeding of orchids is the weakening of turgor in the leaves, falling flowers and the gradual drying of the plant.
Shedding of flowers (at various phases of growth, including undeveloped buds) can also be caused by insufficiently warm room temperature, drafts or weak light.
Important! Physiological diseases are treated - for this it is necessary to eliminate the factor that causes them, but if measures are not urgently taken, this can serve as an impetus for the development of other diseases (for example, fungal).
The list of the most common pests for phalaenopsis includes:
- ticks of various types;
- ants and spiders;
- wood lice and snails;
- podura and nematodes;
To correctly identify the pest, the grower needs to catch one copy on the flower and compare its appearance with photographs on the Internet.
Did you know? No plant family has a wider range of shapes and colors than the Orchid family. The size of flowers can vary from a few millimeters to more than 20 centimeters in diameter. There are colors of petals of any color: white, blue, green, red and yellow. Depending on the species, a plant can have more than a hundred flowers in one peduncle. The color of the leaves can be all shades of green, red, brown and white.
Aphids reproduce very quickly, therefore, in a short time, insects can lead to a halt in the growth of phalaenopsis, the appearance of ugly stems or flowers, and discoloration of tissues. These are vectors of viral diseases, and honey dew secreted by flowers is a breeding ground for fungal spores. Aphid appears primarily on young shoots, leaves and flower buds.
Aphids are very small insects up to 3 mm long, usually green. The grower should quickly take measures to prevent the colony from growing and become a threat to other indoor plants.
Tiny insects prefer heat and dry indoor air. Relocation of aphids to orchids can occur through an open window or newly acquired flowers that were not quarantined.
There is also a species of aphid that lives in the underground part of the stem and in the roots. Their presence can be determined by the wrinkled leaves of the phalaenopsis.
It is worth noting that aphids pose a serious threat only in large quantities. In the case of a systematic inspection of plants, the pest is easy to cope with. After the first use of any insecticide (Actellik, Actara), it is necessary to repeat the procedure again with an interval of 10 days to destroy the next generation.
Did you know? Studies conducted by Harvard University scientists in 2006 prove that orchids grew on our planet already in the era of dinosaurs. The DNA test results of one of the oldest minerals, preserved from the Miocene period, showed that plants already existed in the Cretaceous period - the age of this species reaches 80 million years.
Spider mites are a very common problem when growing any potted plants. Population of phalaenopsis with ticks leads to significant damage and depression of the infected flower. Inhabiting the bottom of the leaf, spider mites suck out the juice from the leaf plate, as a result of which mosaic, yellow spots and a thin, weightless web on their lower side can be observed on the upper part of the leaves. Over time, the leaves become completely yellowed and wilted.
Spider mites are small greenish and red insects, the length of which usually does not exceed one millimeter. They are poorly visible, therefore flower growers learn about their presence only when the first lesions appear on the orchid. Spider mites pose a threat to flowers in adult form and in the larval phase.
The fight against spider mites, first of all, consists in sending an infected flower to quarantine and thoroughly washing the leaves (under a shower or a stream of water). Then there is an immediate increase in humidity and a decrease in temperature in the room where the diseased orchid is located. You can do this: you need to water the flower well, and then put on it a large plastic bag in which the whole plant and pot will fit, and then leave it in this position for 24 hours. Low humidity and evaporation under polyethylene will help to destroy pests.
In the mass population of spider mites, you can use insecticides (Fitoverm, Actellik, Neoron, Apollo, Thiophos). Re-treatment of orchids with an insecticide is carried out after 10 days. We recommend that you learn how to care for cymbidium orchid at home.
Whitefly looks like a small whitish moth, the body length of the insect is from 1 to 1.5 mm. Pests feed on the juice of leaves, buds and young flower shoots. As a result of their activity, small "marble" spots appear on the stems. Both adult whiteflies and their larvae harm plants, causing yellowness and leaf drying. Whitefly larvae can be deposited anywhere in the orchid: on the upper and lower plate of the leaf, in the roots.
Did you know? Vanilla pods are the seed plants of an orchid, and more specifically, vanilla belongs to the varieties of vines belonging to the Orchid family.
These pests feed on the pulp of the leaves, which leads to inhibition of orchid growth, drying out and yellowing of the leaves. The insect prefers to inhabit the bottom of the leaf and in flower shoots.
Mealybug appears in June. Females with egg laying or larvae hide under a convex scaly shield of sand color, located below the sheet. Worms feed on plant juices, thereby causing damage to plants. Phalaenopsis, weakened by the mealybug, becomes susceptible to fungal diseases.
It is worth watching the plants so as not to allow the pest to spread very much. A small amount of it is easier to completely eliminate: a good way is to use vegetable oil on a leaf of orchid with a sponge. After a few days, you need to wash the oil from the leaves and use a brush to remove the scaly shields along with pests choked under them.
Video: how to save phalaenopsis from the invasion of pests
Urgent resuscitation at home
What to do if the plant is already sick and needs urgent help:
- Decay of the root system . This diagnosis can be made by the appearance of the plant: the leaves become soft, yellow and wrinkled. Also, unopened flower buds may fall off on the phalaenopsis. При осмотре корни орхидеи могут оказаться сырыми, мягкими и чёрными. В этом случае необходимо быстро пересадить больное растение в новый глиняный горшок, используя свежий субстрат для орхидеи, и отрегулировать частоту и время полива (обязательно поливать только по утрам). Также нужно помнить о необходимости отрегулировать уровни температуры и влажности в помещении.
- Нападение вредителей, высасывающих соки фаленопсиса . Сразу же после обнаружения вредителей на цветке необходимо с помощью секатора удалить заражённые листки, а затем вымыть оставшиеся листья и стебель орхидеи мыльной водой. Желательно применять хозяйственное или инсектицидное мыло. Если вышеуказанные методы не сработают, то следует использовать инсектицид, при этом наиболее заражённые части цветка всё же желательно срезать.
Как отличить заболевание от поражения вредителями
Симптомы заболеваний и повреждений вредителями орхидей весьма схожи между собой. Присутствие вредителей на цветах можно опознать по характерным повреждениям листьев, экскрементам или кладкам яиц, закреплённых в различных частях растения (листьях, корнях, стебле).
При покупке новой орхидеи здоровье цветка желательно тщательно проверить. Визуально листья должны быть чистыми, без пятен и полос, растения должны иметь здоровые корни. Кроме того, если в доме растут другие орхидеи, то купленное растение следует поместить в карантин, чтобы защитить остальные цветы.
Продолжительность карантина желательно соблюдать не менее трёх недель: этого времени будет вполне достаточно, чтобы вылупился молодняк вредителей из кладки, спрятанной в укромном месте.
Необходимо регулярно проводить визуальный осмотр листьев, почек, стебля и цветов. Это поможет цветоводу не упустить момент, когда на растении появятся вредители или первые признаки болезней.
Для профилактики грибковых заболеваний фаленопсис ежемесячно опрыскивают одним из биологических препаратов — «Фитоспорин» или «Фитоверм».
Важно обеспечить орхидеям подходящие условия выращивания: температура воздуха в помещении — не ниже +15...+18°C, влажность в диапазоне 40–50% и правильный режим полива. Узнайте также как правильно выращивать орхидеи из семян в домашних условиях. Самой лучшей профилактикой болезней и вредителей будет высадка тропических цветов в стерильный субстрат. Для этого покупную смесь проливают крутым кипятком. Когда почвенная смесь остынет и избавится от излишков воды, в неё можно высаживать фаленопсис.
Прекрасные растения требуют соответствующего ухода и заботы от цветовода: орхидеи фаленопсис нуждаются в своевременном поливе, обеспечении подходящим световым режимом, подкормках и защите от болезней и вредителей.