- Kong sunflowers are giants.Jupiterimages/Photos.com/Getty Images
Imagine a sunflower blossom that's bigger than your head, with brilliant halo of yellow petals. That's a Kong sunflower, and it lives up to its name. In the company of other tall varieties with names like Jumbo, Giganteus and Mammoth Russian, Kong is truly a king, reaching heights of 12 feet or more. Washington State University recommends Kong as one of the varieties for growing as a screen, and for its seed size, which makes it good for eating. - Kong seeds are 1/2 inch long, and should be light and plump. Seeds are wide at the top, coming to a point at the bottom. Flat or crushed seeds are usually not viable. The shell of a Kong seed is black-and-white-striped, and thin, but tough. Crack one with your fingernail. Inside, the seed itself is tiny, soft and greenish-white.
- Plant Kong sunflowers in 1 inch of rich, moist soil, in full sun, no later than then end of May. If you're planting them as a screen, set the seeds 2 to 3 feet apart. If you plant them closer than that, they will be overcrowded and flowers will be smaller. Like all members of the Helianthus family, Kong seeds germinate quickly, and you'll see sprouts in less than a week. The first set of leaves splits the shell, and if you watch closely, you'll see the seed casing holding on before it finally breaks apart. Kong's second set of leaves will have the trademark heart-shaped form.
- As Kong seeds develop in the bud, the flower initially looks like a tightly closed fist. As it opens, the center, or seed head expands. The thick stem of the plant pulls water and nutrients to the flower and the growing whorl of hundred of seeds inside. The flower head droops with the sheer weight of them, and at maturity, a Kong seed head can weight 4 lbs. The seeds are white at first, taking on the striped pattern as they ripen. Cut the seed heads off when the blooms fade and hang them in a window to dry. The heads will lighten as moisture evaporates. Brush out the seeds by hand in a month or two, and save them for snacking or feeding the birds.
