[Keith g]

Hi folks, has anybody got a recommendation for using an organic spray for the elimination of aphids and greenfly?

The buggers are all over my dahlia seedlings despite my best efforts

Thanks,

Keith..

[tagwex]

Washing up liquid at 10%, let the the little buggers have plenty of foam.

[Blowin]

Boil up some rhubarb leaves, strain the liquid off when cold, put it in a discarded household trigger spray off e.g. window cleaner, thoroughly washed out, and spray them with that. Watch them fall off.

[Keith g]

Ah thank you folks, I'll try both methods

I'll separate my seedlings and see which works best

Keith.

[Sue Deacon]

Both those work well, or you could try a solution of soft soap (if you can get it). For larger plants and shrubs such as roses you could try my friends trick - breadcrumbs! She sprinkles them on the leaves, it attracts Blue Tits. When they have finished the breadcrumb starter, they move on to aphid maincourse. It must work - she never has aphids!

[tagwex]

Now that's clever.

[Keith g]

+1 yeah that's really clever !!

Keith..

[Greengage]

why oh why are we trying to kill everything, Why are they on your dahlias what conditions exist that encourages them, why not introduce some ladybirds to the plants there are lots around at the moment, Whats this organic pesticides, Pesticides are non discriminatory wheather its greenfly, or ladybirds,

"A recent study compared the effectiveness of a rotenone-pyrethrin mixture versus a synthetic pesticide, imidan. Rotenone and pyrethrin are two common organic pesticides; imidan is considered a "soft" synthetic pesticide (i.e., designed to have a brief lifetime after application, and other traits that minimize unwanted effects). It was found that up to 7 applications of the rotenone- pyrethrin mixture were required to obtain the level of protection provided by 2 applications of imidan.

It seems unlikely that 7 applications of rotenone and pyrethrin are really better for the environment than 2 applications of imidan, especially when rotenone is extremely toxic to fish and other aquatic life.

It should be noted, however, that we don't know for certain which system is more harmful. This is because we do not look at organic pesticides the same way that we look at conventional pesticides. We don't know how long these organic pesticides persist in the environment, or the full extent of their effects.

When you look at lists of pesticides allowed in organic agriculture, you find warnings such as, "Use with caution. The toxicological effects of [organic pesticide X] are largely unknown," or "Its persistence in the soil is unknown." Again, researchers haven't bothered to study the effects of organic pesticides because it is assumed that "natural" chemicals are automatically safe."
www.ocf.berkeley.edu

[Sue Deacon]

Again - breadcrumbs - the only danger there is GM wheat.

Besides, in my 16 years in this house I have seen only ONE ladybird! We just don't get them, or lacewings. We just have the 'munchers', aphids, weevils etc.

[Greengage]

i find that hard to believe, We thought none here until kids went looking and collected 26.

[Sue Deacon]

If we have, they are very good at hiding!

[Good guy]

A balance of natural predators has to be the way to go. I'm encouraging as diverse a fauna as I can, using physical barriers where appropriate and trying to avoid anything else.
I'm interested in trying more of the Nemesis products - has anyone experience of their wireworm treatment? I found the slug one good - but then got a population explosion of baby snails! You really can't win.😫

[Greengage]

James had an article on Wire worms, http://www.gardenplansireland.com/forum/about1277.html
I assume these are imported and not native I wonder the effects they would have on the indigenous Population. Introducing a new Species to solve one problem could result in a bigger problem. i read an article where bumblebees are imported to help pollination of greenhouse crops from Hungary and Poland these are now escaping and cross breeding with the indigenous population, Leading to sterility in native bees and introducing new mites and diseases.

[Good guy]

Thanks for that, Greengage. Yes, I'm well aware of the problems caused by introduced 'solutions' to problems - think rabbits and some kind of toad(?) in Oz, not to mention the varroa mite on bees here.
But the nematodes in use against slugs and those used against wireworm do already occur here. The treatment involves introducing vast quantities of the beastie to tackle the target pest. Once the pest has been greatly reduced, the nematodes reduce in number to normal proportions, too. Or so we are told - and it does seem logical.

[tagwex]

Cane toads.