bugs on brocolli and other seedlings

I've come back from holiday to find little holes and black specs all over my seedlings S ome have little white bugs under the leaves.

What are they? Will a spray of soap and water have any effect?

Whitefly can be a b*gger. I admit to using proprietry sprays, but only when there's a large infestation & usually only have to do it once.

Do they fly off when disturbed, they could be the larger mealy aphid if not.  If the infestation is not too bad these can be squished with the fingers.

These pests secrete what is called 'honeydew' & the black is a sooty mould that grows on it.

There were white flies on them that didn't fly off, under the leaves.Also green ones, and little white edged holes in the leaves.

I sprayed with soapy water twice. I don't know if that helped but the plants seem to be okay now, well apart from the fact i left them in their little pots too long  :roll:

I just saw the pic on the rocket thread and the holes did look exactly like that. They must've had everything on them. I've been thinking perhaps the soap and water wasn't the main help. I had to remove some leaves, perhaps i got lucky and removed the bugs with them?!