[flopsy]

Hi All
What is the best organic way of getting rid of Black fly without using chemicles
Cheers Pete

[Lardman]

It depends what they're growing on. If the plant is robust enough and you can stand doing it; you can make significant reductions in the population by squishing them, just run your fingers over them. Alternatively you can blast them off with a hose or sprayer.

[LottyLouis]

I had oodles of blackfly on my broad beans. On a daily  basis I squished and sprayed with a dilute soapy water mix. I later added a few cloves of garlic to the bottle. I also laid a row of potted French marigolds between the rows. The infestation got so bad I was within hours of digging the whole lot in - then the balance tipped. Hardly a blackfly in sight now, and although there has been some permanent damage, I will get a goodly crop. So out of my mix of remedies - I don't know what did the trick. Maybe the blackfly have just come to a natural end and I know I've been lucky. Others have lost their whole crop. I had minimal blackfly on parsnips and runners and I just squished them. Good luck in your endeavours - but persistence pays dividends.   

[Salmo]

Black aphids have a natural cycle. First they build up numbers. Then predators such as ladybirds, hoverflies and lace wings and tiny wasps build up their numbers and destroy the colonies. In the meantime some blackfly have grown wings and flown to colonise the next yummy crop.

Usually there is a lag between aphid build up and predators arriving. That is when your crop can suffer and you need to do some control. Organic methods allow the predators to catch up. Most inorganic chemicals also destroy the predators and prevent them building up in the crop leaving the aphids free to eat your crops as they wish.

I do not expect blasting with a hose or spraying with detergent does the predators a lot of good but it is more pleasant than squidging big colonies.

[LottyLouis]

I agree Salmo, about killing the predators as well as the aphids. I was concerned I was squishing ladybird larvae along with the blackfly - then I learned what the larvae look like - quite distinctive - so I felt a bit happier. Your post mentions 'organic methods'...what methods do you use?   

[Salmo]

Mainly keep looking at the crops and observing any build up of pests and whether there are predators present. Only bother to control when real harm is being done to a crop. A bit of cosmetic damage does not matter. Usually just squidging but occasionally resort to organic pyrethrun  derived sprays such as PY and then keep stricktly  to the target crop.  Avoid spraying everything on the plot - just in case. Only spray in the evening when the bees have gone home.

[LottyLouis]

Only spray in the evening when the bees have gone home.

I'd be afraid the bees might want to stay out partying...with the ladybirds!   

[AnneB]

I only have one broad bean plant affected by blackfly - odd, given there are another 60 adjacent to choose from!  Still I am not complaining.  I did a bit of squishing, then lots of ladybirds appeared.  No more blackfly.