I use Safer Brand Insect Killing Soap,32oz $5.97 at Lowe's.
Has worked for me for 5 yrs.

Hi funnylady :) I saw you are building another one? How fun for you..Did you run out of room already? Please post pics when you do... I wanted to post that... I thought it was neat how they had insect control wayyy back when..:)

I've been using Safer Brand Insecticidal Soap but they keep returning. Having a problem with whiteflies too. The Safer Soap kills them, but they keep returning. They seem to reside in the hibiscus most of the time, and just run out to pester the other plants for fun. Cheryl

Yes you have to reapply all the time, there are always new eggs haching.

I've had lots of white flies, spider mites, and aphids in my greenhouse. Cinnamon oil spray seems to work fairly well on all three. I've found that air circulation helps with white flies too. I think air circulation is key with any greenhouse and avoiding pests. Also, I've noticed that if I get rid of all near dead or very unhealthy plants the problem is greatly reduced. I've realized that sometimes it is worth sacrificing one plant you like that is hosting all of the bugs to save the other plants you love. Sometimes it's too hard to say goodbye to certain plants though, in which case I trim them back as far as possible and try to nurture them. I recently composted several plants that were very unhealthy, but had strong sentimental attachments. I am horrible at getting rid of stuff, but I have to admit it felt kind of freeing... Sometimes I'll use a small amount of orthonex in extreme infestations, but ultimately sprays aren't going to get rid of severe, continuous pest problems. I find it helpful to re-evaluate how I'm growing my plants when I encounter issues. I tried predator mites before and they help a lot, especially if they establish a solid population. I want to try predator nematodes too - I've heard they work well. It seems to be all about finding a balance. Bugs are always going to be around, just don't want them to get out of control. You probably know a lot of this stuff, but it helps me when people remind me of things I may have forgotten or not tried in awhile. I might try burning some oak leaves sometime- thanks! Good luck!

Marathon, or any systemic containing imidicloprid.

Has anyone heard of letting ladybugs loose in the greenhouse? I have a small 4' X 6' soft plastic green house set up and have an aphid problem. Just have various peppers in it. I was thinking of getting some ladybugs and putting them in it.

You could try that, but before you spend a lot of money on ladybugs, you might just try a soap spray, like Safer. Spray the undersides of the leaves, then repeat in about 5 days and you will make great progress.

I have aphids in my greenhouse too, and the soap spray keeps them in check. I have heard that ladybugs tend to just leave a greenhouse when given the option.

For my greenhouse, the very best aphid control is ant control. It's the ants that drive the aphid outbreaks.

karin-
I'm not convinced that ants drive aphid outbreaks. The reason ants are present with aphid infestations is that the aphids secrete a substance high in sugar and the ants "mine" these substances. If you eliminate the aphids, the ants disappear.

I started a thread on the ant-aphid relationship a couple of years ago, with the happy outcome that in my greenhouse at least, I have figured out a solution. (borax ant traps)
:)

Here is a link that might be useful: older thread about ants and aphids

Note about sweet basil: Aphids hate it. Where it is touching or very near pepper plants, those plants have virtually no aphids on them. The secret is to grow it close to other plants and let it touch them. Sweet basil will get quite tall, at lease 3 feet. It grows about the same rate as peppers. It is probably sufficient to put one plant between pepper plants at regular spacing, and train them into the peppers as they grow. **** The following Insecticide formula is better and much cheaper than that spray soap you buy.
My formula for Ivory soap insecticide is: Using a vegetable peeler shave 1 bar pure ivory soap into a pot containing 10 quarts water. Simmer til dissolved. Cool and strain into a 2 gallon sprayer using a very fine strainer. It might not all fit but my sprayer holds all but a cup or so. The mix will suds so I just keep pouring until nothing but liquid is in the sprayer. I set the sprayer in a 5 gallon bucket to catch the overflow. This mix is quite a bit stronger than most I see on the net but mine actually works. With those weaker mixes in a spray bottle you will be chasing aphids daily, hand turning the leaves. This is time consuming. The sprayer has enough volume and sprays in all directions so all you have to do is run your wand through the plants and you are quickly done getting even the underside of the leaves. If you are on a budget you have just found your best hint. You will have to re spray as another said eggs keep hatching. This spray has not damaged any plants and I soak them.

Why not look for the ant colony and destroy it.
Ants are known to take care of aphids due to its sugary butt.
Destroy the ants that protect the aphids from it's natural predators and use a soap spray.

This is a very old conversation so I hope this site is still active. I have an aphid issue in my greenhouse. I have tried many of the solutions that have been discussed here from the past. I have cut down infected plants, killed the ants, sprayed soap & water mixes and use safe sprays. I spray every other day and they just come back again. I cut down peppers that grow next to basil and the aphids started walking on the basil.

My question is, has anyone since the last post, found a real answer to putting an end to aphids?

From my experience, all you can do is control them, there really is no end to them. The problem is their life cycle also includes a winged form of adult, which will arrive to lay more eggs, even if you think you have gotten rid of all the soft bodied little crawling suckers.

I`ve used pure rapeseed (canola) oil for the last couple of years, its proven very effective for keeping the common foes aphids, mites and whitefly at bay.. Add 60ml of oil to a spray bottle, top up to the 1 litre mark with water (240ml oil in 1 us gal). Spray the plants liberally. making sure to get the underside of the leaves. If necessary, repeat every 3 days until the infestation is cleared. Be careful not to spray the plants in full sun or you`ll risk scorching the leaves.

Thank you for responding to my question.

Took a day-long seminar on greenhouse management from the local botanical garden. They have an acre under glass and will soon be doubling that. Best take-away was their 'solution' for soft-bodied insects like aphid: A couple of drops of Dawn and a capful or two of isopropanol in a quart sprayer. Swirl to mix, you don't want suds. Works well, even on the crawler stage for scale.

Cheers

I tried Dawn in water and Alcohol in water but never the two together. I will test that formula and report back. Thank you.

50-75 years ago my Dad used Nico Fume in his flower growing operation. It was very effective for aphids. It came in a can that you lit with a sparkler through one of two holes in the bottom, then you would walk backwards with it while the nicotine smoke billowed out and filled the greenhouse as you retreated. The advantage was coverage. Everything in the greenhouse got covered over and under, top to bottom. There was no such thing as a beneficial bug in a greenhouse back then. Don't know if they still make Nico Fume. Suspect EPA found an excuse to ban it.

According to google, it was used to kill all sorts of insects back in the early 1900's. I don't think anyone would eat anything in the greenhouse today if it was smoke bombed with nicotine. I don't think you will find it for sale anyplace in the USA.

Nicotine - as an insecticide - is still heavily used in agriculture today, albeit in synthetic forms. It's relatively cheap, long-lived and one of several possible causes of colony collapse disorder for honeybees. To bees, it is highly toxic and persistent, easily carried back to the hive by foraging workers. A recent aerial spraying for Zika-carrying mosquitoes wiped out millions of bees in Georgia. It wouldn't have been so bad if the knuckleheads in charge had scheduled the spraying for night when the bees would have been somewhat sheltered in the hives. Instead, the idiots scheduled the spraying for when the bees were most active. That's criminally stupid....

Wow. I didn't know it is still used. So, what about food crops? Is it still used on them?

Imidacloprid, the most common applied nicotinoid, is effective against many insects and even fleas on pets. It can be added to irrigation water, though it is somewhat less toxic to mammals and birds than other insecticides like carbamates or organophosphates. Neonicotinoids are used on about 95
percent of corn and canola crops in the US, the majority of cotton, sorghum, and
sugar beets and about half of all soybeans. Also, they have been used on the
vast majority of fruit and vegetables, including apples, cherries,
peaches, oranges, berries, leafy greens, tomatoes, and potatoes, as well as
cereal grains, rice, nuts, and wine grapes. Imidacloprid is possibly the most widely used insecticide worldwide.

In addition to outright toxicity, sub-lethal doses of neonicotinoids may interfere with the bees’ ability to forage, learn and remember navigation routes to food and back to the hive, which in itself is a death sentence.