Hi Shannon,
Watermelons are very rewarding to grow - it's so much fun to eat the yummy, juicy fruit that you grew yourself! They do need hot temperatures, lots of sun each day, and plenty of water. Depending on what part of zone 5 you live in, it can be a challenge to grow them, esp the large ones, like what you saw in the video. Many northern growers have success growing them in a greenhouse, but the smaller varieties should work well for you as long as you get them started early in the spring after your last frost date. I like to plant my seeds indoors to give them a head start. Keep me posted on how they grow for you in zone 5. Thanks for watching, Shannon!