While gnats may seem to be only a nuisance they can seriously damage a plant’s structure if they are left unopposed. It is important to keep in mind that gnats are drawn to houseplants that are over watered and left damp. Along with to much water decaying plant debris can serve as another attraction to gnats. It is important to keep in mind that sanitation and careful watering still may not be enough to keep gnats at bay. But before you give up and simply throw out your plants there are ways to deal with those pesky gnats. Here are more ways to get rid of gnats in houseplants-
· Insecticidal soaps-Insecticidal soaps (these are known as potassium salts of fatty acids) are one of the most commonly available houseplant insecticides. These are used as diluted sprays (with a one to three percent concentration) and can help control many houseplant insects including fungus gnats. It is also interesting to note that many liquid hand soaps and dishwashing detergents can also have insecticidal effects, although there is potential for plant injury with such treatments.
· Horticultural oils-These oils are diluted sprays of oils (petroleum distillates, mineral oils) and are some of the most useful insecticides for houseplant pests. These highly refined oils act primarily by smothering developing larvae.
· Neem-Some commonly used houseplant insecticides are derived from seed extracts of the Neem plant. This is a commonly grown tree that is found in many tropical areas. Neem seed contains materials that can disrupt insect growth and is useful for control on developing gnats. Neem seed also contains oils that may be used in a manner similar to other horticultural oils and is generally sold in products labeled as containing “clarified hydrophobic extracts of neem seed.”
· Pyrethins and pyrethroid insecticides-Pyrethins are a common ingredient that is found in many houseplant and garden insecticides. These chemical compounds are a natural product derived from flowers of a certain (pyrethin) daisy. One of the biggest benefits to using pyrethins is that they are fast acting, have a very short persistence (a few hours), and low toxicity.
There are also several synthetic components to this type of pesticide. Some of these also have a fast acting ability and have a short persistence while others may persist in active form on the foliage for several days. Consultation with a plant specialist at the local nursery can help you determine which is the right agent for fighting your infestation of gnats.
Since most of the above methods are considered pesticides it is crucial that the following guidelines be used. By following the cautions listed below when using pesticides on houseplants you can work to avoid exposure and plant injury. These guidelines are:
· Be sure to only use pesticides that are specifically labeled for use on houseplants. Most yard and garden pesticides do not allow this use.
· If possible, be sure to take the plant outdoors before spraying to minimize pesticide exposure within the home. This will also help prevent pets or small children from inadvertently breathing in the pesticide.
· If you are using aerosol sprays, do not apply closer than 18 inches to the plant or injury may occur from the spray. This precaution should appear on most label use directions.
· It is best to avoid treating plants that suffer from environmental stresses such as temperature extremes or drought to minimize potential plant injury. It may be best to quarantine any infected plants until they are healthy enough to treat.
· If you are using a pesticide that has granules or plant stakes containing DiSyston use extra care when watering. Excess water can carry this insecticide as it puddles or drips. It is important to keep in mind that this product is extremely toxic.
· Be sure to always read and follow instructions on the label!