I have to build some 6' x 2' planter boxes, I'm not sure what's going to be planted in them; probably "garden-y" stuff like oregano, basil, etc.
I know how to build things but I know nothing about plants except that every one I touch dies (I even killed my cactus).
I'm basing the boxes on instructions I found here:
My questions are:
- How big should drainage holes be and how far apart should they be spaced?
- The screen at the bottom will be vinyl, nylon, or some other inert plastic. How fine should the screen be? Does it matter?
- How deep should the boxes be? I don't really care about minimizing volume, I just want to make sure the plants have a nice place to grow.
The box will be cedar (non-treated). Underneath the boxes will be a few inches of open air, then concrete.
I'm assuming the person I'm building them for will be filling them with a bit of gravel and some soil.