My black garden planters look faded, can I spruce them up a bit?

[Fluffycloudland77]

There made of a stone/composite type material not plastic.

They don't even get sun till after midday.

Blackboard paint, or a Matt black stone paint. If they're non-porous you might be able to use an enamel which would be glossy.

I spray my old pots with
www.wilko.com/specialist-paint/rust-oleum-painters-touch-satin-spray-paint-black-400ml/invt/0413341

Brings them up like new and so easy to do. They also have a good range of colours so if you fancy a change or something brighter then you can do that too.