Exterior stain or sealer? That should do the trick. Paint or stain will really help and if you make sure it's exterior, it should last longer.

Not trying to steal the thread but will spray paint work to paint wicker? I just bought a wicker dresser at a yard sale and I want to paint it white.

Yes, it will. My aunt had a several sets of wicker around her house (she had a larger old home with a few porches). She picked up most of the pieces second hand and they needed work. They sprayed all of the furniture pieces with glossy white spray paint. I do remember my Gran saying they bought one of those triggers that you attach to the can because their hands hurt from pushing the nozzle for as long as they had to! LOL

I have a bunch of wicker I use on my front porch. It is fairly protected, but still is out to the elements. I power washed it, primed it and then painted it with exterior white paint. I tried to use a sprayer, but ended up painting it all with a brush. I totally destroyed a couple of brushes, but it turned out GREAT! And after a year of being outside, looks like I just did it! Was something I put off doing for a couple of years and now wonder why! It was work, but the results were SOOOOOOO worth it. Looks like NEW wicker!

Just do it......it will look bright and clean and just like new. Really worth the trouble!
Good luck!
Julie