AH, NUTS … THEY ARE GNATS! By Rose Crawford

Sympathetica Lily needs your sympathy
when gnats get into the soil.

Does your houseplants have uninvited guests? Did you try Rose and Flower Insect Killer or Insecticidal Soap only to find dead houseplants later? It may be cute to have little decorative critters on garden stakes in our gardens, but it is entirely different when our houseplants get inhabited against their will. So, here’s a tip from the gardeners to help our indoor plants:

Firstly, we need to understand what gnats are and where they come from.  Believe it or not, gnats are formed from fungus in soil of houseplants. It’s a very common problem no matter where you live…gnats invariably inhabit a houseplant despite most seemingly good efforts. Here is the culprit or major cause of fungus-related gnats on houseplants…OVER-WATERING! Gnats love to breed in damp decaying organic matter, which is a common ingredient in houseplant soil.

Schefflera is susceptible to Fungus Gnats,
if over-watered. 

Gnats lifecycle is about 4 weeks, especially in houses or areas where warm temperatures are maintained inside. Gnats go through a metamorphosis – from egg to larvae to pupa to flying adult. When you see flying adult gnats hanging around your houseplants, they are depositing their eggs into the moist soil. The cycle then repeats itself. While there are sprays for gnats, you must read the label to find the one spray specifically formulated for “Fungus Gnats”. Most gardeners recommend you not spray at all. 

TIP: Let your plants dry out as much as possible and at the same time, trap the adult gnats. You can do this with yellow sticky traps that hang (purchased in most hardware or garden stores). You can also make them cheaply by getting bright yellow construction paper, (gnats are attracted to yellow), and coating it with Vaseline.  You could also layer a coating of dry sand on top of your soil to try and trick the gnats in thinking the soil is dry and they don’t want to lay eggs. Once the gnats are gone, you can scrape off the sand and feed your houseplants with MiracleGro liquid, but be sure to keep them on the drier side.  Let your houseplants tongues hang out “WANTING” water without drying them out too much.  MircleGro also sells a Moisture Control Soil that assists with over-watering or under-watering.

A Golden Pothos is no longer "Golden" if
over-watered. Gnats attract to yellow even in leaves!

Be diligent in fighting the adult gnats and you’ll win the war, plus your houseplants will still be alive! 

Source: The Californian Newspaper-Sunday September 23, 2012 Section F