Pests and DiseasesBugs create a host of problems and can seriously damage a collection if left untreated. Scales, mealybugs, aphids and mites are the most common orchid pests. You will find that bugs are attracted to certain genera. For instance, mealybugs like phalaenopsis and bifoliate cattleyas, while scale prefers cattleyas and cymbidiums. Aphids are attracted to the buds and flowers of dendrobiums and oncidiums, but they do not discriminate between orchid genera. Spider mites will show up when there is a lack of humidity especially on dendrobiums, oncidiums and cymbidiums. Always keep a close eye out for bug damage. They like to hide under leaves and sheathing and, if left untreated, they will quickly spread through your collection. By removing old sheathing once it becomes loose, it will be easier to recognize the early signs of an insect problem. Scale depletes chlorophyll leaving yellow spots on the foliage. They also love to feast on the tender eyes at the base of the pseudobulbs. Aphids will leave a sticky residue on the foliage below where they are eating. Spider mites can be identified by the silvery scarring they leave under the leaves. The good news is that most orchid pests are easily exterminated. Home and garden sprays will provide a long list of bugs they will kill. We recommend spraying the plant, then manually cleaning it as much as you can with a Q-tip or toothbrush, followed by another treatment of spray. Follow up treatments after five to seven days may be necessary to fully eliminate the problem. Schultz, Bayer and Ortho all carry a good line of sprays that are available at any garden center, hardware store or home improvement warehouse. For a less toxic approach, we recommend using denatured alcohol, neem oil or insecticidal soap. Remember to always be extra careful of what you spray, especially on the flowers, and always follow the manufacturer’s instructions to prevent plant and flower damage. Slugs and snails chew flowers and buds as well as the tender new roots and growths. Bait is readily available and will do a good job of ridding your collection of these pests. Ants can be a problem, especially when moving your orchids back inside in the fall. Orange Guard, a citric acid product, is a good way to eliminate these pests. However, if they are down in the mix, you will need to drench the pot with an insecticide or repot the plant. Other orchid problems, like rot and fungus, can be treated by first removing the infected area with a sterile tool, then applying a fungicide spray or powdered cinnamon, which is a good natural fungicide. Improved air circulation can help prevent a reoccurrence of this problem. Flowers that have botrytis (small dark spots) should be removed to prevent spores from spreading to others blooms. Any orchid exhibiting signs of a viral infection should be totally segregated as contact with diseased plant fluids will cause the virus to spread and may contaminate other plants. Any questionable plant should be tested and if it tests positive, it should be destroyed as there is no cure for orchid viruses. This is why it is so important to use sterile tools and equipment when handling your plants. Human contact and chewing insects are also vectors for spreading viruses. We hope these tips will help you to be successful with your orchids. There are many orchid books, magazines, periodicals and internet sites that can help you to become a better grower. We also recommend that you go to the American Orchid Society link at the top of the page for individual culture sheets for all types of orchid genera. You will find growing orchids to be an exciting hobby. However, a word of caution, orchids are extremely addicting! Once you purchase your first plant, you will be ‘hooked’ for the rest of your life!