This workaround does not work for me on 4.18.3, but putting all the foliage in it’s own sub level and unloading it allowed me to bake the lighting for the landscape.
I’m not yet sure if baking both the landscape level and the foliage level at the same time works or if the results of baking only the foliage lighting separately are visually ok, but I’ll keep you guys updated as my testing progresses.
Greetings
Andi