Like humans and animals, plants need both water and nutrients (food) to survive. Most all plants use water to carry moisture and nutrients back and forth between the roots and leaves. Water, as well as nutrients, is normally taken up through the roots from the soil.
So, for example, a 3-month old puppy should be able to hold its urine for approximately 4 hours in a pinch. This means that if you have a properly toilet trained 4-month-old puppy that, theoretically, can hold its urine for 5 hours, and you shut that puppy in a crate for 6 or 7 hours, you are courting disaster.
I would never tolerate a dog peeing at will in the house after 6 months old, if he can hold it in the crate for more than 3 hours, then he can most definitely hold it everywhere else for the same amount of time. He apparently sees his crate as the den, but not your entire house.