I sprayed with Neem about 3 weeks ago on my late dormant apple trees for the first time so results are still pending. I used the cold-pressed one recommended on Michael Phillips' website. It is true you need to put the bottle in warm water to melt as it was semi-solid at room temp as well as adding soap. It has instructions provided. I used a squirt bottle and kept shaking it. I am more concerned about scab here than aphids. Do you have plantings to attract benefical insects? Farmerfred dot com came up on a search in regards to that topic.

I "believe" I've had success with a two part attack. I heat my plant water to 50C, and make a mixture that is one part hydrogen peroxide and 3 parts water. For really large pots, I would place the pot in a large enough bowl/saucer to hold water, and add water to the bottom to come up 2 inches, then water from the top with more of the 50C hydrogen peroxide water. Supposedly the bubble action of the peroxide is enough to kill off the larvae near the surface, and the heat of the water does too. I would always find dead whitish larvae on the outside of the bottom of the larger pots from the bottom watering. This has to be done continually, with all plants, over a period of a time. My numbers began to decrease, then all disappeared. Now I see a few back again, but I've been making nursery purchases, and keeping in the house because it is too cool to keep outside (coleus, potato vine, begonias etc). I just keep up with warmer water (now at body temp, and a smaller percentage of hydro peroxide, about 1 part to 4). Apparently, herbs and plants that have scented leaves to not appreciate this treatement, but I have not had one houseplant or outside garden plant die from it. I purchase the 3% mix from the local big box store, cheapest I can find if 1 litre/$2. Nearby reputable nursery purchases the 30% stuff (which would apparently eat the skin of your hand in seconds if applied! Yikes!) and apply a week solution to their plants for part of their bug control method. It bubbles as it sinks through the planting medium, and fluffs it up, sometimes too much, so the soil it puffed up like a muffin or cupcake would when done baking in the oven. So once I feel I've got the #'s of gnats under control, I weaken the mixture (1 to 4 or 5 water), then it doesn't foam up so much. I am now addicted to watering this way, especially the succulents in winter, gives them a drink but doesn't leave them wet for long, soil dries out faster. Summer they all get straight water. I also operate some indoor worm bins, and one know that one for certain is a breeding ground for those pests, so I keep it wrapped in a bedsheet that I change with each feeding. I freeze the sheet with the flies trapped in it to kill them, then shake 'em out on the deck or in the tub (winter) and rinse them away and start over. But in the general area of the house, except for the odd couple I've noticed in the past 3 weeks (due to not being able to say no to taking home bedding plants because it's too cold for them to live long in the Canadian Tire greenhouse here!) I think I've got a good handle on them. ~kioni~

Spraying leaves is a common technique and simply the most practical and effective method. From a certain (even low) number of plants you can't avoid it anyway. And, you don't only want to remove a few specimens, but have your crops completely free of them and protect not affected plants from invasion as well. Which clearly makes sense with a repellent, - doesn't it? and how would you control or inhibit the reproduction with such surgical intervention? I have used Neem oil extensively in the past and leaves don't seem affected at all, even with frequent spraying. There are no reports of any problems with "clogged stomata" due to Neem oil, as far as I know, - except sporadic speculations about the possibility ;-) In fact "Neem oil" used in relatively low doses in combination with an emulgator (preferably with a wetting agent) isn't that oily. I guess the portion that MAY get into your system or nutrient solution is simply neglectable in most cases and hence wouldn't affect it. An alternative (with regular aphid visits or an exposed/affected area), like here in the tropics is in fact protecting the crops with a smaller aphid net application or an aphid net house. PS: the remark about "aquaponics without fish" was in fact a play upon words. It was meant as an allusion to the fact that the term aquaponics doesn't actually contain any hint about fish. One more "new term" that sounds cool but isn't very descriptive or from the shoulder at the end. A bit like bio or "bio-dynamic" that became "organic" eventually - which don't actually describe nor differentiate properly. Because these plants and products don't distinguish from other cultures as described, as others aren't less dynamic nor non-biologic and certainly not inorganic. I know this is going a bit off-topic but the latest slogan I discovered displayed at the entry of some local super market that mainly provides imported food for expatriates was: "ORGANIC AWARE SHOP". Not sure (doubt it actually) that this was invented here in Thailand, but what the heck does that actually mean? Are they truly "aware" people, - or do they officially admit that they have finally passed the state of denial, regarding a movement they can't oppose for ever?! A new form of the "argument of conversion"? LOL Just thinking loudly, ignore O.T. if not interested in some of my thoughts....

This has been a big issue for me this year too. During the cool very wet Spring, infections were so bad I lost some clumps, and others were set back severely. Most have made a good come back. I am trying to figure out how to be preventive. I replaced the soil for the ones that had the worst infestations. Currently I am spraying once weekly with neem oil, hoping the active ingredients will soak into the rhizomes and reduce further infection. New growth is green and spotless, but I imagine when chilly rainy season returns that will not be the case. They are in raised beds. Drainage is good. Air circulation is good. I removed other plants that might impair circulation or shade the irises. Not sure what else to do. I would like to give them some fertilizer for a boost of growth, but I fear doing so last year promoted fungal infection, so I'm not doing that now. For old leaves with a few spots, I am leaving those on and spraying with neem. For leaves with a lot of spots, I removed them.