Often when we walk into a greenhouse our gaze sweeps across the sea of green and we admire the colors, the light and the variety of plant life. We should however follow the admonitions from Les Mis and ‘Look Down’ to investigate where it all starts. In the soil. There are several pests that inhabit this dark underworld, and using biocontrols for these pests is the cornerstone for many programs.

Thrips are common greenhouse pests and challenging to control with chemicals. They are tiny and hide in between leaves and flower bracts. They are easily overlooked until the telltale signs of feeding occur: discolored or distorted leaves, stipling, silvering and premature leaf drop. Using yellow sticky cards in the crop can alert you when they show up and trap them, decreasing the population.

Growing banker plants to rear Aphidius colemani is like putting money in the bank. Instead of buying Aphidius on a regular basis, you can produce your own on barley or oat grasses that have been inoculated with cherry oat aphids.

Dalotia are quick, aggressive predators and are always hungry. They are used to target fungus gnat larvae and thrips pupae, but the Dalotia diet also includes shorefly, root aphids, root mealybug, moth eggs, organic matter and mold.