Aphid Control

[Ivor]

I recently discovered some aphids in my lettuce crop. I have a suspicion that they came in with some new lettuce plugs that I recently planted as they are the most afflicted.

What is the general method of handling insect problems with aquaponics?

Thanks!

[arthoz]

Soap water with oil and spray them evenly on your plants but make sure you use mineral or vegetable oil and use soap which is safe, not the kind with an antiseptic solution, it might endanger the fish. Though our local botanist told us to use laundry detergent.

By the way, try to keep ants away from your plants. Ants and aphids are like shepherd to a sheep. Ants actually protect aphids and harvest food (sort of like nectar) from aphids. I even heard that ants spread aphids...not sure if it's true...ants, wonderful insects aren't they?

[bigdaddy]

Should you spray at dusk or early in the morning?
I heard with oil sprays you should to minimize the risk of burning the leaves in the heat of the day.
Perhaps others could confirm that for us please.
Cheers

[Rew]

Certain flowers and herbs, when planted near your crops can also deter aphids. Marigolds are one I know of, it may be too late now, but could prevent future outbreaks.

[arthoz]

Sorry for the late reply, been busy lately...

Well I guess it's a rule of the thumb and a big no-no here to spray your plants with water at noon or at any time the sun at its hottest since those droplets of water instead of nourishing your plants, becomes hundreds of tiny magnifier that intensify sunlight and sunheat. Think of it like you are lying under the sun and someone uses a magnifier glass to focus sunlight on your skin, I guess the plants would feel the same too.

Maybe, I'm not sure about it but I have my own suspicion that oil does the same and a layer of oil on your plants could cause it to heat up but for the case of an organic pesticide, I don't think you should use too much oil, just enough to help spread the solution onto the plants and on those pesky bugs. You don't have to spray your plants until it's covered with a layer of glistening oil. To think of it, the organic pesticide I've concocted doesn't even feel oily at all. A spoonfull to a few litres should be enough, to be sure there's a lot of info on the net of the type of mixture.

[MarkDW]

Hi Everyone
A very low-tech but safe answer is a strong jet of water from your hose. Also if you don't mind getting your hands dirty, rub the aphids off. Most of us look at our systems daily, so when you see them get rid of them straight away. The ants in Sydney love farming aphids and protect them so you will often see them running over the aphis infested branches harvesting the honeydew that the aphids excrete. The honeydew also encourages fungal problems so another reason to get rid of aphids quickly.
Cheers
Mark

[nwestwood]

Aphids are my nemesis. I have to use a variety of controls to keep them in check.

1) Never, Never, Never bring garden plants into a greenhouse. I've made this mistake over and over. Last fall it was two bell pepper plants I wanted to save. NOT smart as our garden plants have all these pests, but have natural predators that help control them. Once they are in the greenhouse, population explosion.
2) Like the first rule, I'm very very cautious about bringing plants in from the local Walmart or nursery. Check them ever so carefully. The best method is starting your own from seed, then your safe. If I have any doubt, I will treat the plants with something deadly to insects and keep them in a pot for a couple of weeks before transplanting them into the system.
3) I use beneficial insects to keep the white flies, aphids and gnats in check. I'm on a monthly schedule where a hobby greenhouse mix is sent to me monthly. There are notes on this on my personal website.

When they flare up: (for me that includes all the citrus trees and other things in the greenhouse, not just the aquaponic system)

1) Prune off the infested part, if you can, early before it spreads.
2) High pressure water will knock them back, but not stop them.
3) When all else fails, I mix 50% rubbing alcohol, 50% water, and 1-2 teaspoons of neem oil in a squirter bottle, mix well and carefully spray the undersides of the infected plants, VERY carefully as you don't want the overspray in your fish water. This will kill off everything it touches. This is a lot less toxic than most sprays, but very effective.

[SanJuanCap]

Hi Ivor, here in California ladybugs are used to eat the pests off the plants. They will hang around your garden until the bugs are gone, then they fly away so don't expect to have them around for more than 2-3 daysif you don't have a greenhouse.