In article , jane jane@moonrose.
demonmapson.co.uk writes

Derris (rotenone) is a recommended spray or powder for raspberry beetle.
It's sort-of organic, as it can be used 'as a last resort' for several
things eg flea beetle, but the official HDRA organic solution is to remove
mulches and rake the ground around canes after fruiting in the autumn so
the birds can get in and eat the overwintering adult beetles.

IMHO the HDRA organic solution would be by far the best method in the
longer term. It tackles the problem on the plant and in the soil,
whereas derris/rotenone will only kill off living beetles, leaving
infestation in the ground as eggs or pupae to re-appear in subsequent
years. The chemicals sprayed will also remain on ripening fruit and
will enter the food chain - exactly what organic methods aim to prevent.

When a gardener or grower decides to convert from chemical to organic
methods, they may need a little help to tackle problems remaining in
their plants or soil. Organic standards recognise that and make
provision for it by introducing a conversion period, but produce grown
during that period cannot be sold to the public as organic.

HDRA guidelines for recreational organic gardening give qualified
acceptance to certain methods and materials to help gardeners through
conversion. Those are only intended to be used 'as a last resort' as you
rightly say, and they are not suitable for regular use in an organic
garden. Derris/rotenone is listed as unsuitable amongst many other
materials such as Bordeaux mixture, soft soap, Pyrethrum, Quassia,
copper based substances, Borax, disinfectants etc. etc.

Full details are in the HDRA booklet 'Guidelines for Organic Gardening'
available from their website at: www.hdra.org.uk
--
Alan & Joan Gould - North Lincs.