Just to clarify here, you don’t need to use foliage trellis for bat farming or spider farming; that’s just a space-saving preference for layout efficiency.
My farm isn’t built to save space, it’s built for symmetry to include and organize all colours of trellis. My gleambow foliage is far too precious a resource to turn into foliage trellis for colour mutations, so I opted for the expanded layout. 200% crop yield on paintable normal trellis blocks surrounded by normal foliage, tangle, wood & wicker.
If you’re wanting black bats, I suggest just making a new section with plain black trellis if you can’t find the black foliage you’re seeking.