Planning on making my own, moveable planter boxes - what liner should I use?

Location: Nor Cali, Coastal Region Santa Cruz/Monterey Bay.

I have recently been able to get some very nice pieces of pine and cedar. They have been most likely been supports for transporting larger shipping items.  I also have some IPPC stamped wooden palettes.  I was thinking about bashing together some wooden planter boxes to use for growing herbs.  The ideas is to move them into the garden (on drip) in the spring summer fall and then into the green house (yet another project) in the winter.

I was thinking about lining the boxes with either some weed barrier that I have at hand or some other material that would let water through but keeps the dirt (mostly) in.  The thinking was that I don't have to worry about fitting the planter boards tight to keep water and dirt from running out the sides, rather than the bottom.  Any suggestions as what is best to use?  Also suggestions on folding it so that it fits a square or rectangular planter would be appreciated.  TIA!

Landscape (weed) fabric is commonly used to create a breathable zone between the wood and the soil, to slow down wood rot. In a dry climate, it may perhaps affect water retention; but there are other ways, like biochar, to mitigate that.

I made a raised bed out of pine fence boards (mine isn't moveable).  I lined it  with a good quality weed cloth.  It is working beautifully.  The main thing to remember is the good quality part.  I got a huge roll, 4' X over 200'  for about 28.00$ at Sam's Club. It works great, the last roll I bought lasted me a couple of years.  A time or two I bought some other stuff and was very unhappy with it.  You want the kind that is like a thick cloth.    Good luck to you.

I am leaning towards felt.

I have made a few 25 inch cube planter boxes every year for several years now for my tomato plants. I space the boards 3/4 in apart and line the bottom with about 4 inches of leaves. I then stand straw and hay up the sides while filling the boxes with my soil.
 Although it is not permanent, I dump soil into garden beds every fall and mix up new stuff every spring and start over. Even in the hot steamy south the hay hold the dirt in all season long and plant roots are air pruned when the grow through it. I also find earthworms travel up through the leaves on the bottom.  Always full of them when I change out the soil.
   

On some small containers I used those coco coir pots you can buy.  I buy them at the end of the season super cheap. I stretch them out, and patch them together to cover the area I want covered.  It works quite well.  It keeps the soil in place, let's the water through, and helped reduce the heat in the metal containers I s used.

Thank you all!  I didn't think about the earthworms.  I will have to tinker a bit and maybe figure out how create some sort of worm hole (ha!) covered with some coarser webbing that allows for the youngens to enter and make a home!   Time for some trials and testing.