Alright forget it. If anyone ever finds this issue, here’s the solution:
As the sun is rotating down, you should ALSO set the “light source” (or whatever the sun is called, i can’t remember) intensity to 0.01, by lerping it or whatever you wish.
If the sun has any more intensity below the landscape (or maybe other geometric floors too), the foliage will start to glow at the base.
UNPROFESSIONAL and nonsensical, but here you have it.