Controlling Fungus Gnats with Biochar
by Jim Hole
Fungus gnats are one of the most annoying insect pests of houseplants.
For those of you who may be unfamiliar with fungus gnats, they are tiny, delicate, black flies that inhabit potting soils. Female fungus gnats can lay anywhere from 50 to 300 eggs during their short one week lifespan.
The eggs are laid in moist areas that have a high percentage of organic matter and high microbial activity because the larvae (worms) feed on fungi (thus the name fungus gnats) and decaying plant material. Now, because peatmoss and compost are so common in potting soils, fungus gnats do extremely well in these mixtures provided the soil surface remains reasonably moist.
Once fungus gnats have become established, they are difficult to control. Today, there are no registered pesticides for use on domestic houseplants to control fungus gnats and other control methods like yellow sticky traps help but won’t eradicate these annoying pests.
However, finally there is one non-chemical fungus gnat control - available for the first time this year - that does an excellent job. It’s called, Pure Life Biochar and it’s a rich, black, charred bamboo that is spread on the surface of potting soils to eliminate fungus gnats.
Because Biochar is inert and doesn’t degrade like organic matter, fungus gnats hate it and won’t lay eggs on or in it. Not only that, but biochar looks fabulous as a ‘top dressing’ on potting soils.
It also absorbs fluoride from tap water, reducing tip burning on those tropical plants that are susceptible to fluoride toxicity. A layer that is spread out on the soil surface and about 2 cm deep for small pots and 5 cm deep for big pots is all that you need.
So if you are fed-up with fungus gnats give Pure Life Biochar a try!