1. Beets are botanically the same as chard. The Latin name of both common vegetables is Beta vulgaris, and both came from the same ancestor. Over centuries, people selected the plant either for big, fleshy roots (beets) or big, fat leaves (chard). They're still sexually compatible and can interbreed with each other today!
2. Beet seeds are actually several seeds fused together, so even when you plant "one" seed, often more than one plant will sprout from it. They're called multigerm seeds (as opposed to monogerm), and they occur in plants with flowers that grow with their petals fused together with neighboring flowers. That's how the tiny flowers of beets and chard grow, so their seeds are also fused together. In a diverse cultivar like rainbow chard or our new 3 root grex beets, each seedling that sprouts from that "one" seed you planted can be a different color!
3. Beets take two years to make seeds. They are biennials, meaning they grow a 
beet the season you plant them, but they must go through a period of cold (winter) before making their seeds the next year. The beet we eat is actually a giant, starchy storage structure meant to store nutrients through the winter for the beet so it has enough energy to sprout leaves again in the spring, send up a flower stalk, and make its seeds. Cold weather and then a return to warmth is required to signal the beet it's time to send up a flower stalk, but weather that's too cold can freeze and kill the beet while it waits in the ground through the winter. We at SRSC have had a hell of a time figuring out the magical combo that allows our beets to get cold enough to break dormancy in the spring, but not too cold to kill them. Storing them in a walk in cooler or root cellar doesn't always get them cold enough to break dormancy the next season, while letting them stay in the field can mean they freeze and/or rot. In the Skagit Valley in Washington, where they grow a massive amount of the world's beet seed, they dig up the beets from the seed farms and barge them to Whidbey Island, where they bury them in big pits to wait out the winter before bringing them back to the fields on the mainland for replanting. This also helps break disease cycles, which our cold winters here do a good job of on their own...if only we can keep our beets from freezing along with the diseases that plague them!
4. Beets don't need bees to pollinate them. They are wind-pollinated plants. As such, they don't make big, showy flowers. Instead, they make tiny little inconspicuous ones that spew out copious amounts of tiny pollen that blows around in the wind and sticks to the stigma of neighboring tiny ass flowers. This is why each seedling that sprouts from the "single" beet seed you planted can be a different color. Each can easily have a different dad of a pollen grain that fertilized it.
5. Beets and chard aren't the only commercially-grown varieties of Beta vulgaris. Sugar beets are huge business in southern Idaho and throughout the Intermountain West. They are like beets, but white in color and they grow to be massive (sometimes a foot across), but they're not very tasty. While they are one of the few plant species to have been genetically modified, the way companies process sugar beets to extract the sugar doesn't leave any genetically modified DNA left in it. Mangels are a lesser-known type of Beta vulgaris grown mostly for cattle feed. Like sugar beets, they're big and not that tasty.
