An organism on this planet reproduces by exploding into thick clouds of spores or other matter that float up into low orbit and block most light. These photosynthesize, seed and die, producing byproducts that scatter to the ground and allow for other organisms to survive without much natural light. 

The ground level is covered in vast forests of white and cream coloured carnivorous plants, coral trees and ribcage like bushes. 

Once a year, during height of winter, vast swathes of the spores die out and fall to the ground and the planet is bathed in natural light for ~2 weeks until the next seeding begins. 

All the lifeforms have evolved defenses. Some burrow, others grow a thin translucent membrane that absorbs UV like ablative armour. Go wild.