You can get packets of sunflower seeds with the rest of the seeds (flowers, veggies) in the spring. Plant according to the directions on the packet. They are not perennials, and they will be damaged by frost (spring/fall). We usually plant seeds in mid-May or a bit later. As their name says, sunflowers like lots of sun. The fancier colors and varieties are done the same way as the regular yellow ones. Just check out what is available and buy the ones that strike your fancy.
We have had problems with squirrels digging up the young seedlings and ripping off the seed heads when they develop, and the bunnies (aka terrorists) will chomp on anything. We have grown single plants in pots on the deck, but those have needed staking or tying to keep them upright in the later stages.
If you put out sunflower seeds to feed the birds in the winter, there are usually some “volunteer” sunflowers that pop up near the feeders, and if they end up in out-of-the-way spots, we leave them to develop as if we had planted them ourselves. You can even save out some of the seeds from your big bags of bird seed and plant those in your garden in the spring.
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