On Sat, 8 Jun 2013 09:58:14 +0100, Sacha wrote:

I was just talking to Matthew about some people using washing up liquid
to spray whitefly and he's adamant that it has to be Fairy Liquid! He
commented that 'all that eco-friendly stuff is no good' and the
constituents cause leaf scorch. So, for what it's worth I pass it on.
Not that I'm suggesting for one second that anyone should use a washing
up liquid for anything other than its intended purpose but we know how
some people like to bend the rules.....

I use any old brand of washing up liquid and it works on whitefly and
blackfly.