Because natural photosynthesis is more complex and is in service of growing a plant, so it only needs to run for a little part of the day. It also takes water a

Because natural photosynthesis is more complex and is in service of growing a plant, so it only needs to run for a little part of the day. It also takes water and needs to be protected from pests, diseases, and herbivores. But it also sequesters carbon, and if planted well can be entirely self sustaining. So, neither is better, both are good. We need to plant more trees and place more solar panels.