Procedural foliage won't spawn on landscape

I’m running into a strange problem where I can spawn foliage on a static mesh (like the default floor in a level) just fine, but when I try to put some on a landscape nothing happens. I can literally just move the spawner over a few inches from the mesh to the landscape and bam, foliage gone won’t spawn there.

What gives? This happens regardless of importing a heightmap, or just generating landscape without one.

Can happen when trying to paint foliage too.

Thanks for any suggestions

Solved my own problem. The landscape needs to be painted before the foliage will spawn there. It won’t work on just a plain, untouched landscape freshly made. Had no idea. So if anyone else runs across this question with the same problem paint your landscape and see if that helps.