There are an estimated 1600 species of Begonia around the world and the group includes herbs, small shrubs, and some epiphytes, all with certain similarities. The most common is the Wax Begonia. Who would have thought that Begonia leaves are edible, raw or cooked. The flowers are also edible, but usually eaten raw. While Begonias are edible, there is some debate about how much of it you should eat at once. The leaves taste sour and somewhat acidic. Tossing a few begonias into your salad will give it an interesting tang that many people will find appealing.The sourness in Begonias is due to oxalic acid.. Oxalic acid reacts chemically with calcium, forming an insoluble and indigestible crystal called calcium oxalate. The oxalic acid in begonias will bind with calcium in your digestive tract and render it unusable to your body. This basically means that other calcium that you may have consumed in some other food is wasted. Apart from the theft of calcium, the issue with calcium oxalate is that it is what most kidney stones are made of. You will often see begonias paired with sour cream or cream cheese as an alternative spanakopita or cheese spread. It is commonly used in salads in China and Indonesia and made into a sauce for fish and meat in Indonesia (according to Green Deane).Begonias have been used in herbal medicine as an astringent as the sap is anti-bacterial. It is an excellent source of vitamin C and has been brewed as a tea and used to treat colds, stomach upsets and sore throats.Begonias are monoecious, meaning that male stamens and female pistils are contained in separate flowers on the same plant. Flowers are most often pink, though sometimes white or red or occasionally yellow. The leaves of most species are asymmetrical, one side larger than the other. Leaves have prominent veins and sometimes a reddish tinge.The oxalic acid in Begonias doesn't pair well with pets. They are toxic and will typically make your dog drool and or vomit. Unless he has eaten a lot, he will be fine.Image: KENG MERRY MIKEY MELODY and Vahan Abrahamyan/Shutterstock