outdoor cedar project. what kind of finish should I use?

Whatever you put on it will require periodic maintenance. Leaving it to gray naturally will not.

Watco makes an exterior product, I think Cetol does. These are oils, not film finishes. For further options I’d search “oil finish boats” and you’ll get lots more and likely better info.

Cedar, being very porous, likes to take in moisture, so sealing up as much end grain as possible with the oil will be a good practice.

Kindly,

Lee

-- "...in his brain, which is as dry as the remainder biscuit after a voyage, he hath strange places cramm'd with observation, the which he vents in mangled forms." --Shakespeare, "As You Like It"

Make sure you line the inside of the planter to avoid soil contact on the cedar.

linseed oil works well; there are many oils that work well; some people thin out the linseed oil and give it a few coats; it will only last a season.

cedar needs nothing and sealing the end grain like Lea is a great idea. solid color stain works well.

Thanks for the input guys. I think I will just leave it natural after looking further into it. Sounds like a lot less maintenance, plus after getting more into the project it looks good that way.