Cleaning pots/planters with a bleach solution?

Cleaning pots/planters with a bleach solution?

An article I read somewhere recommended washing old pots and planters etc in a 'bleach solution' before re-using them the following season - does anyone have a recipe for this bleach solution, or an alternative? I was lucky also to find five polystyrene boxes at my local market which had been used to transport packaged corn, they look brand new but as I'm going to use them to grow vegetable seedlings from seed they'll probably need 'bleaching' too, right?
The garden is snowed in

The garden is snowed in

Work in progress – HELP!

Work in progress – HELP!

My room is very cluttered and messy

My room is very cluttered and messy

Some kind of lily.

Some kind of lily.

Mystery flowering shrubbery…ID help requested…

Mystery flowering shrubbery…ID help requested…

Fixed!

Fixed!