Control fungus gnats on amaryllis effectively and easily with hydrogen peroxide and sticky traps! If you watched my passion for amaryllis video where I discussed planting, caring for, and reblooming amaryllis you may now be wondering what to do about the most common pest of Amaryllis - the dreaded fungus gnat. Fungus gnats are dark bodied flying insects who measure about 1/8 inch in the length and thrive in moist soil where there is an abundance of organic matter and fungi for the larvae to eat. Fungus gnats have four developmental stages – egg, larva, pupa, and adult. The adult females lay their eggs into moist soil that emerge as larvae in four to six days. The larvae are slender, legless maggots with translucent bodies and dark heads. This larvae feeds on fungi, decaying plant matter, and plant roots in the soil for approximately two weeks before pupating, and three to six days later they turn into adults. The adults live for one week with the females laying up to 200 eggs in their short lifetime. Since the entire life cycle can be completed in 3 weeks, overlapping generations can be present at any given time.

Plants suffering from severe fungus gnat larvae feeding can show signs of wilting, loss of vigor, poor growth, and yellowing. A small population will rarely do significant damage, but in large numbers or at large growing facilities this can be a serious problem.

The best method of control always starts with prevention. Since fungus gnats need moist soil and organic matter to survive and thrive it’s important to avoid or eliminate these environmental conditions. Here are five steps to make your houseplants and home an unhospitable environment for fungus gnats to live and reproduce.

Avoid overwatering and allow the planting medium to dry between waterings. Wet soil is fungus gnat central, so take care to let at least the top 1-2 inches of soil dry between waterings.

Always use new, high quality potting soil when planting up bulbs or houseplants, and never use soil from outside – this will surely result in multiple problems.

Provide good drainage. Often pots without drainage are used for aesthetic appeal, but it’s hard to judge the amount moisture in a watertight container. Instead, use a plastic pot with drainage holes placed into a watertight cover pot that appeals to your taste. Then you can lift the plastic pot out to water and allow it to drain before placing it back into the cover pot.

Take care of any clogged drains or leaks. The key to solving a fungus gnat infestation is to eliminate any sources of built of moisture where gnat populations will reproduce and thrive.

Avoid plants potted in cocoa coir or peat as both of these mediums hold moisture and are prime breeding grounds for fungus gnats. Buy only healthy plants from reputable nurseries and inspect the soil for any signs of pests before bringing them home.

Even if care is taken to uphold these steps, fungus gnats can still enter your home. They can travel in on clothes, pets, food, and new houseplants, just to name a few. If you see them becoming a problem, take the prevention steps listed above and begin this organic treatment to rid yourself of the fungus gnats – both the adult and larvae stages.

Control fungus gnat larvae with hydrogen peroxide. Whenever it’s time to water, use a solution of one part hydrogen peroxide (over the counter 3% hydrogen peroxide), to three parts water to control the larvae. The solution will foam and fizz as it enters the growing medium – this is normal. Continue to use this hydrogen peroxide/water solution in place of your regular watering until the situation is completely under control. Depending on your level of infestation this can take a few waterings/weeks. Hydrogen peroxide is an antifungal agent that eliminates fungus gnat larvae, soil fungus, and oxygenates the planting medium. It’s important to use new and/or properly stored hydrogen peroxide for this remedy to be effective.

Control adult fungus gnats with yellow sticky traps. The flying adult fungus gnats will be attracting to the yellow paper and will become stuck on the adhesive and die.