[joannazoo]

Hi being new to all this veg growing thing, I am trying red cabbages and brussels in my allotment, and the small bed at home. At home they are doing very well (very huge more like) but the allotment ones were put in later and seemed to have succumbed to insect infestation. I have looked it up in books, and it is similar to aphid infestation (yellow curling leaves, slower growth) there are small eggs visible under the leaves, which also look like aphids, but there are black beetles hanging around looking menacing   which look too black and too solid to be aphid, they are also more of a beetle shape (think female stag, but 2mm long) than my experience with aphids suggests.
So my questions are:
What are they?
How can I treate this organically?
How can I treate this full stop?
Have I lost the crop?

[WG.]

Any possibility of some piccies please?

[joannazoo]

not at the moment...

[WG.]

not at the moment...

Then I'm guessing with this answer ...

The beetles may actually be your best organic solution since some species are carnivorous.

Might the eggs simply be Cabbage White Butterfly?  No matter, I suggest you rub them off.  Most probable is Mealy Aphid - spray repeatedly with garlic spray.

[WG.]

This might help with identification
http://www.rhs.org.uk/advice/profiles0504/mealy_cabbage_aphid.asp

[Aidy]

Yellowing leaves maybe the old cabbage root fly and by chance the eggs are from something else, to me it sound like CRF. pull one up and look at roots to see if any of the maggots are munching the roots.

[joannazoo]

Definately not cabbage white butterfly - wrong shape for butterfly eggs, and they are covered, so a butterfly couldn't get through the nesh.
I hadn't thought about the beetle being a predator... that could explain a lot! I will however try lifting one to see the roots, to check there as well. If it is that, is there anything I can do?
How go you make garlic spray? ( i have searched both these topics and come up with nothing)

[WG.]

How go you make garlic spray? ( i have searched both these topics and come up with nothing)

See garlic spray in the Glossary of Terms in the Welcome forum  

All please feel free to vote in the poll & to contribute further terms (with or without definitions)

[Aidy]

If it is CRFly then those that have been attacked are gonna's, lift and burn them, when you plant your brassicas put collars on, if you do a search for cabbage collars there will be loads of threads covering the subject, I am afraid as I have just found out that even with collars some may still be attacked, I have just lost 6 purple broccoli. All wilted with yellow leaves. The root shoot have lots of roots coming off the main, if attacked it can look a little stumpy.