Unless you are growing water or bog plants, you need bottom drainage or weep holes at the base of the planter. Otherwise, you want to fill the planter with a uniform mix of potting soil - no drain rock at bottom, no barrier, no garden soil, just a good quality potting soil.

This looks like an excellent situation for some type of bamboo - the planter is a bit too restrictive for much else that will develop any height for privacy. Equisetum can work also.

May we see the face of the planter?

Hi, thank you for the replies.

The bottom of the planter is open to the original soil, it is not sealed.
Is that sufficient drainage, or would I not want the water to drain underneath the patio and wall footing?

I am adding a picture showing the entire planter and wall.

P.

We're doing a job right now where someone 15-20 years ago installed masonry planters against the lower level of a home with the theory that a soil bottom and no other draiange was fine. We're now core drilling drain holes at intervals along the wall base, prior to the contractor replacing everything on the house that's rotted. Just FYI.

Ok, sounds like bottom drainage is a good idea then.

I've seen both flexible corrugated and rigid drilled pipe used, what would you suggest I use?

Rigid perforated wrapped in filter cloth -

A note on soil - a potting soil will decompose ( shrink) and compact a bit too fast. I'd suggest a planting mix.

We're working a somewhat similar project . photo attached.

Wow. I know this was a really long time ago, but what did you end up doing? I have this planter outside of my home and I need to figure out a way to get the water out when it rains. Otherwise we're getting it tuckpointed often.