Cedar wood roof

[helpneeded]

Hi I have cedar wood shingles on my roof and they are starting to get some mildew or moss growth... I really dont want to change the roof because that just means money i dont have... Is there a way to clean the roof.... ive heard using bleach in a hose end sprayer and spraying it all down... Would i have to use a brush and clean or is there a better way...
some peole say using a power washher but i dont have one ....should i do that?

any advice would be of great help
thanks again

[mrcaptainbob]

Roof mold

I have heard that placing a strip of copper along the ridge helps this problem. Supposedly the copper leaching down the roof stops the growth. No plants like copper. I wonder if copper tubing would work? Sprinkling copper sulphate up there would also do it, but that's only temporary.