I'm planning on building a wood planter box for some edible herbs. (Similar to this; in Maple and a bit more squarish.) I already plan to glue the wood with Tidebond III as it is waterproof. My question is how to seal the wood itself from the water.
So far I've seen the following suggestions :
What would be the best? Should I consider Cedar instead of Maple?
I have made a few exterior window boxes and none lasted long with the wood in contact with the soil. I would make the boxes of whatever wood and finish matches yor kitchen. I would seal the inside with an exterior grade urethane. The idea is to protect the wood from the dampness and occasional water spill. I have had the best long term results by using a plastic container to hold the soil. The box is just a decorative holder for the plastic containers
There are many finishes that work, but many wear and are rotted over time by the contact with the wet soil and roots. If you use any cyanoacrylate glue (superglue) as a finish it'll do that. It's waterproof, strong and cheap. I use it to finish my pistol grips. The ones I have on my personal carry pistol I have had for 4 years, never refinished since the first time. Never buffed, sanded, refinished, recoated. and it takes heavy abuse and (as gross as this will sound) has withstood years of being in contact with my sweaty body. That will work for you.
