GreenCoast Hydroponics Blog

I have been battling aphids at the Long Beach Store. It started innocently enough. I started eggplant seeds under some fluorescent lights in the front window of our store. The seeds did fine and i got about 99% of them sprouting and growing nicely. Once they had their first 'true leaves' i went ahead and transplanted the cute little seedlings into our recirculating hydroponic drip system. The plants are doing ok, but not great because they are covered with aphids! I had ignored the ants all this time coming in under the front door. I didn't realize these ants were farming aphids on my eggplants. Apparently the ants have been bringing them in and milking them for honeydew. As if they were cows.

Aphids are small, soft-bodied insects that suck plant fluids with their piercing-sucking mouthparts. They may be either winged or wingless, and their color may be green, yellow, brown, red, or black, depending on the species. Most species have a pair of "exhaust pipe" structures called cornicles projecting out of the hind end of their body. The presence of cornicles distinguishes aphids from all other insects.

Aphid colonies are often located on the undersides of leaves. Curled, distorted leaves and sticky honeydew (aphid excrement) on leaves indicates the presence of aphids. Black, sooty mold may grow where honeydew has been deposited. Aphids transmit viruses that can cause plant diseases, but eggplant is not as susceptible to these as are some other vegetable crops. Fortunately, eggplants can generally tolerate moderate feeding without significant damage. Young plants are more susceptible to aphid damage than older plants. Aphid-infested seedlings can be killed or severely distorted.


Guide to Commercial Eggplant Production ANR-1098, New July 1998. J.M. Kemble, E.J. Sikora,E.H. Simonne, G.W. Zehnder, M.G. Patterson, all at Auburn University

Ok. So i definately have aphids. no question about it. But it does sound like by eggplants can handle some aphids without totally giving in. My plan of attack will be to knock down the aphids with insecticidal soap. I am going to spray on a regular basis for a couple of weeks. Then i will release Lacewings Larvae into the growing environment.

The first thing i have tried is Safer Insecticidal Soap. This soap is basically a physical insecticide that breaks down cell walls and basically bursts and dries out bugs. It is supposedly very effective against soft bodied pests like aphids. I have been using it every few days for about a week. I have seen a reduction in aphids and the tell-tale signs of dead, dried up aphid bodies. It seems that they need regular treatment because it seems rather mild and i haven't seen a total , because the aphids that are left immediately start reproducing again and if i don't treat again than the population will start booming again.

The nice thing about this product is that it breaks down quickly and is pretty inexspensive. It is a good choice if you don't mind spraying regularly.

Stay tuned for my adventures with neem oil...