I have a raised bed in front of my house with a brick retaining wall. The problem is that I can't get paint to stick to the brick long-term, even after priming first. The previous owners of the home apparently had this same problem. Ideas?
Paint may not be adhering due to moisture in the raised bed.
See if you can find some Mineral coating type paint it is made for masonry.
If you can't find it you can make a lime wash for the brick or use a Lime Paint.
Lime wash will only last about 2 years of a raised bed planter.
Brick needs to breath, it really should not be painted.
I agree with keith 100 percent , never paint brick , ever
It needs to be sealed from the BACK side.You would have to remove the dirt, clean the brick and then coat the surface. There are petroleum based sealers which are commonly used to seal exterior basement walls before they are back filled during construction.. This is a fare amount of work, but the only hope of getting paint to stick to the front. Latex paints are preferable to oils for masonry uses, as they breathe better.