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.
O nce your young puppy gains the ability to control his bladder, you can begin potty training him outside so that he'll learn to eliminate in the area you desire, rather than in your home. Generally, this occurs at around 12 weeks of age, when the average pooch can hold his bladder for around four hours at a time between potty breaks. Training can take three to four months, depending on your particular pup. Pups are unable to eliminate on their own until they reach between 3 and 4 weeks of age.