I’ve had excellent results using sub irrigated planters - the linked vid gives an explanation of the concept and details of how to build.
I made 6 on my roof in BK using standard storage bins, working well for three growing seasons so far.
i love to do favors and leave gifts for my future self. i switched out my purse this morning and found an unopened thing of hi chews and $40 that i intentionally left for myself ~6 months ago because i knew it would be a happy discovery someday. today was the day!