Put down 35 square metres of decking last summer. still looks mostly in tip top condition apart from a few green areas around entrances etc. just tried jet washing but it's not budging. is it a case of getting down and dirty with scrubbing brush or is there an easy solution? I know there are specialist products but I'm not sure this warrants it.

Algon

Bucket of soapy water and a stiff broom. Throw plenty of water on the deck ahead of yourself and then keep dipping the broom in soapy water, pressure wash or hose the soapy/dirty water off when you've finished scrubbing. I do this every year before re-treating the deck and it works a treat.

Seem to be struggling to find a good decking treatment that lasts more than one year though :o( Anyone able to help with this??

Last time I googled this the consensus appeared to be that a dilute bleach solution left on for a few hours worked just as well as the expensive deck cleaning stuff you can buy from DIY stores. Works for me.

Yep bleach works pretty well. Get some value bleach from the supermarket. I think sometimes pressure washers just force the algae deeper into the wood / slabs. They can damage the wood too.

I use muc off and a broom excellent bleach is nasty

Decking , rats like to live under decking dont they?
A big bonfire should do the trick.

My wife told me she wanted decking in the garden, so I took her outside and stuck the head on the bitch

I cleaned my Decking with my pressure washer a couple of weeks ago but found I had to get the nozzle really close otherwise it didn't shift anything.

Have just painted it with Cuprinol Decking stain treatment but at £25 for 3 litres from Homebase it better be good.