Orchids are not very susceptible to plant pests, but sometimes pests do occur on orchids and may cause serious problems in orchid care and growing directly or indirectly as transmitting virus infection, for example. In this topic, we discuss the most common orchid pests and orchid pest control in general.
Aphids are very common plant pests. They may come in yellow, pink, green, black, and red colors. They’re sitting on new growing leaves and stems and sucking plant’s sap.
Snails and slugs are eating the leaves and roots, scrubbing the surface and making holes. These mollusks are acting during nights, and hide in a day time. One of a control measure might be an immersion of a pot into the water heated to 105-1150F.
Spider mites (Tetranychidae) attack lower surface of thin leaves predominantly, causing appearing of small white spots and bleaching out of the leaves. They produce eggs every day, which are getting matured during about 5 days, and a new mite becomes an adult within a week.
Pseudo spider mites (Tenuipalpidae) are often very harmful because of their small size: they may make a lot of problems before they are noticed. They can live on both upper and lower leaf surface, making no cobweb. White spots are gradually changing into brown wounds. The eggs are getting matured in a week, and mites become an adult in a fortnight.
Scale insects (Diaspididae) are ones of the most serious and firm pests. They are sucking the plant sap sometimes injecting toxins. They produce rigid, roundish, more or less flattened scale of 2-3 mm in diameter around their body. From several dozens to several hundreds of eggs may be put under one female scale, sometimes a vivipary takes a place. Young insects are active during several days than they lose their legs becoming immovable. From 3 to 7 generations are possible per year.
Mealy bugs or coccids (Pseudococcidae) are slowly moving parasitic pests sucking the plant sap. Adult coccids can reach up to 8 mm length; they are coated with white or yellow pounder. Some species are viviparous, but most of them are putting the eggs in wool-like sacks. The eggs get maturated in 4-10 weeks, and the insect becomes adult in 2-3 months. As coccids may also damage another greenhouse plants, which means that secondary infection often occurs.
Wood-louses (Porcellio, Armadillidium) are eating organic rotting products predominantly. If they meet good conditions for them, they propagate themselves quickly and make considerable damage eating tender and juicy plant parts. They are especially dangerous for young plants and seedlings, which may be even killed by them.
Small greenhouse flies are dangerous because of their larvae which transform a substrate for orchids (bark pieces) into humus-like substance, preventing the proper aeration of roots. The roots get weaker and then die off. Dead root areas become inhabited with the larvae which penetrate into alive zones promoting further dying off of root system.
Inappropriate care often can lead to orchid diseases and susceptibility to pests, so how to care for orchids is always important. For example, Phalaenopsis care must be different from Cattleya care. Your plants shouldn’t be stressed. It’s always reasonable to remove old leaves, flowers, and other debris because some pests may hide there. The best pest control is always simple preventing. So, check each your new orchid thoroughly before you add it to the area where your orchids grow if you notice any pests you should remove them so as not to induce further spreading of pests. If you notice that some of your plants have been infected you’d better separate them from healthy ones.
All methods of getting rid of pests can be divided to organic and non-organic. Organic pest control, first of all, is simple removing of pests from your plants. Sometimes you can remove aphids by simply blasting them off with a jet of water. Sometimes you can easily pick the pests off individually from an orchid, especially such pests as snails. Using suspensions of essential oils or such ingredients like garlic and paper is also considered as an organic method for bug control. Also, you can release predator insects, such as ladybugs, into your plants. Ladybugs eat aphids, spider mites, mealy bugs and other parasitic insects.
New pesticides aren’t very toxic for humans, but still for many people using pesticides at home doesn’t seem very wisely. But if you decided to use pesticides, always follow the label directions. Systemic insecticides are preferred to use – they penetrate into a plant and spread throughout the whole plant. All pest control products must not be expired. There are a lot of different pest control companies on the market.
A good solution for dealing with insect pests is using a rubbing alcohol. It’s not 100% organic method, but it’s not considered as a pesticide as well. You can use a paper or a toothbrush wetted with 70% rubbing alcohol and wipe off bugs from leaves, stems and other parts of a plant. Pay attention to places where leaves are attached to a stem and areas around bases of the leaves because bugs often like such parts of the plants.
So, orchid pest control is a complex thing and should include preventing, identifying and controlling methods.
Also, read about orchid diseases.