Pre weathering eastern white cedar shake siding shingles

[NJOracle]

I sided my house almost 20 years ago with eastern white cedar - extra. Now I have to replace about a dozen shingles in various locations. Of course the existing shingles are now gray but the replacements would be white. I don't want to stain the replacements, just speed up the weathering process.

In Googling for Weathered Cedar shakes, I have come up with a couple of posts that say to mix 1 lb of baking soda in a gallon of water and paint the solution on the shingle. Let dry in the sun and then repeat until you get the desired weathered affect.

Has anyone tried this? If so, how many repetitions does it take to get the weathered look?

[hrhofmann]

Did you try to contact the authors of those posts?

[NJOracle]

Not yet. I was looking for independent verification.

[Arnie Goetchius]

I am experimenting and it seems to work. I have coated half of a shingle so I can show the difference in a photo.

[rjjksbates]

I am now faced with re-shingling a barn but not all sides. Looking to weather the shingles so it will blend better. Did you try the baking soda method and did it work? I was wondering if Vinegar would work as well.