Wednesday, September 30, 2020
GROW PRACTICES: Aphid Defense 101

Photography by Illustrated by Rachel Fleischman

GROW PRACTICES: Aphid Defense 101

An Aphid Bank Introduction


Aphids are one of the most common plant pests. This holds true for cannabis grown both indoors and outdoors. Because they can give birth to pregnant young, aphid populations can grow very fast in a short time.

There are many aphid species that can attack cannabis, and it only takes a few of them carried in on your clothing or through air intakes to infest a crop. Aphids are a sucking insect and can compromise a crop very quickly, as well as spreading viruses. Early warning signs include leaf stippling and the honey dew, actually their poop, showing up on leaves.

It has been my experience that outdoors, with a little patience and strong nerves, you can count on natural predation to control populations. Ladybugs, lacewings, and wasps will often clean up an outdoor grow within a few weeks. You must be patient and believe in the natural world for this to work. Do not just spray at the first sign of an aphid.

For indoor grows, other techniques are needed early, and prophylactic control has given me the best results. I have been using an aphid banker plant system with great success. This method employs parasitic wasps to control aphids. These wasps, Aphidium colemani, work all day and night, searching the entire plant and laying eggs in the aphids. Once hatched, the young wasp consumes the aphid from the inside. Exit holes in the aphid mummies are a telltale sign the system is working.