Try some of that new Deep Cleaning 409 stuff....that is some good stuff.....If that doesn't work...try the classic bleach and water.....Have fun!

Believe it or not, I use the same car soap I use to wash my car and it works perfectly. gets all of the stains out with just a little scrubbing!

vinegar and hot water

I use Ajax, water and a stiff nylon bristle brush. It works but is labor intensive.

if u have a pool throw them in for about 12hours the chlorine cleans it.

weslys bleach white spray.

water and bleach. or water and dawn dish soap. Also if you have, or can rent a pressure washer those work good too.

with water.

plastic chairs exposed to sunlight, rains and dirt are likely be stained hard,if maintained with bleach,soap and water weekly you can have have it as always new preventing dirts and molds that penetrates pastic and become part of its color deeply penetrated for a long time of exposures outside,if bleach and baking soda overnight does not work,try to sratch it with steak knife then peel it like a potato then try to use sand paper(the finer one)wash it with laundry soap and wallahh you have a brand new garden chair!

Use plain dish soap and ammonia. Works great.

They make a cleaner for them now, but I don't remember who makes it. Check your local Home Depot, Menards or lawn and garden store.

Any good soapy mixture.. I also like to use SOFT SOAP and NOTHING NOTHING NOTHING more abrasive than that on the plastic

MR. CLEAN MAGIC ERASERS and water

Mine actually became dull and scratched from cleaning them over time. There is a plastic cleaner in a spray bottle available at the Home Depot, manufactured by Zep. But, I got sick of the effort last year and used the new Plastic Paints spray paint (at Lowes) and sprayed them black last year. They have other colors, but I found that the chemical bond created by the paint also seems to repell water and other stains. I simply hose them off and they look great!

Softscrub with bleach!!

mr clean magic eraser

i use mr clean erasers they work fantastic get them at the dollar general cost is 2.50 for two to a box they clean anything try tem out good luck

I USE CLOROX CLEAN UP, LET IT SIT AWHILE, USE A SCRUB BRUSH IF NEED TO, THEN RINSED OFF WITH THE HOSE.

bleach and hot water

Use a product called Spray Power,it is excellent for outside stains

Mr. Clean Magic Eraser..it's pretty much amazing.

CIF AND SOFT CLOTH THEN RINSE WITH FRESH TEPID WATER

I used CREST WITH WHITENING and water worked great

Mr Clean magic cleaner. its like a white sponge it works well on just about everything.

GREASED LIGHTNING!!

Blast them with a hoes pipe

bleach rocks!!!!