[farmergiles]

Looks like spidermites to me. (same as the pic below)

Dilute soap solution applied to the plant especially to the underside of the leaves.

Ladybirds eat them.

Nematode worms (available from hydro shop) kill the eggs I think.

You can get smoke bombs to kill them, but it`s tricky to get rid of all the eggs as well so you might have to repeat what ever method you use.

They probably got in on your clothes rather than in soil.

They like hot dry conditions.