Use a large kitchen knife to cut a thin slice from the bottom of the watermelon—this helps it stand up straight! If you find a watermelon that sits upright on its own, you can skip this step. Then cut a hole in the top of the watermelon. Create a wide opening, angling your knife toward the center as you push down; cut this opening the way you would cut around the stem of a carved pumpkin.
Use a large ice cream scoop to hollow out the watermelon. Scoop out the red part of the melon, scraping all the red and pink insides until you're left with just the green rind. Don't let the insides of the watermelon go to waste! They might not be as pretty as sliced or cubed watermelon pieces, but they're perfect for a summer smoothie or watermelon sorbet.
Use fresh flowers from the garden or a pretty store-bought bouquet to finish this showstopping centerpiece. We love the way the pink and purple flowers pop against the watermelon shell and the greenery in the bouquet. Opt for bright summer colors, or go with white and red flowers for a patriotic 4th of July centerpiece. Don't forget to add water!