Would be interested in a solution to this! I just tried to knock as many of them off as I could last year, nothing special!
What worked for me last year when i had 2 serious infestations
1 - Scrape off all the eggs under the leaves with a small paintbrush followed by spraying them with a mild fairy liquid / water mixture, you only need a small drop of the fairy liquid <- that got rid of the first lot but make sure as soon as you notice 1 theres probably hundreds of eggs under the leaves
2 - Make another solution up with garlic cloves and some of the hottest chillies you can get hold of, mash everything up and add to the water and spray away, apparently aphids hate capsaicin lol
last resort is chemicals which will do a good job of killing anything but always a last resort for me
Update on mine isn't good........................
Woke up one morning last week and the compost had completely dried out and all 30 odd plants were DEAD, all 30 odd plants ffs.....
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i suppose that will teach me for using ****** B%Q see compost and not john innes
Sooo... had to order some mature plugs from here -
http://www.worldofchillies.com/chilli-plants/buy-chilli-plants.html - got a very good service from these guys
Picked 12 in total to last me this year as i can't be arsed germinating any more seeds, I'll post some pictures up when i get chance to take them over the weekend