Being a Kansas boy by birth, it seems only natural that I would have a strong affinity for sunflowers. Kansas is, after all, the sunflower state. The wild form of Helianthus annuus grows up and down the roadsides and throughout natural areas across the state. This is not the giant garden form of sunflower that we often see, but a shrubby, multi-stemmed, small-flowered version--the wild form--that sometimes covers acres of land in a sea of yellow blossoms in late summer.
Today, some of my favorite garden flowers are the perennial sunflowers that put on such a spectacular garden show in the summer and fall of each year. These are true perennials that come back from the same rootstock year after year to touch the sky with their golden yellow flowers. They're not all towering giants, of course, but some of my favorites are. For example, the plant in the photograph is Helianthus 'Marc's Apollo' and it's a skyscraper! Not for the faint of heart and not for the small garden, this graceful giant may reach upwards of 12 feet by the time it's in full bloom in mid- to late September. I've made room for it, even though it's a little tall, because the show that it puts on is truly stunning--HUNDREDS of butter yellow flowers for nearly 6 weeks from September all the way 'til frost.
Helianthus salicifolius, the willowleaf sunflower, is another favorite. It's also a giant, but if you pinch the tips out of each stem about mid-June, it will flower at 6 feet or so instead of the nearly 10 feet it can reach otherwise. It has, in my opinion, the most beautiful foliage of all of the sunflowers--almost threadlike in its appearance it is so slender. It's a fantastic texture to add to the perennial garden even when it isn't in bloom.
A little-known species, but another that I simply wouldn't be without is Helianthus microcephala, the little-headed sunflower. Very bushy, almost shrubby in habit, it has a broader leaf like those you would see on Rudbeckia 'Goldsturm' or Echinacea. It flowers a little earlier in the season, usually beginning in July, but the show goes on for months. It is not uncommon for it to still be flowering at the beginning of October when, as luck would have it, it's foliage turns burgundy red! Yellow flowers and burgundy-red foliage! Wow! It's still not a small plant, but it's worth the space.
If you would like to have a sunflower in your garden, but simply don't have the elbow room for one of the larger fellows, look for Helianthus angustifolius 'Low Down'. It's a true genentic dwarf and when in full bloom will only be about 18" tall with a 2-foot spread. I'm usually not a big fan of dwarf forms of plants that should be tall and willowy, but this one's a winner! I promise!
Plant some of these later flowering sunflowers with other spectacular late summer and fall beauties such as Aster oblongifolius 'October Skies' and Callicarpa americana and you'll have a combination that will have the traffic stopping in the street to admire your garden's beauty.
Please note that there really is no need to deadhead your sunflowers. It will do very little to extend their flowering season and besides, the birds (especially the goldfinches) will go absolutely crazy over the seed as it ripens on the plant and this brings an entirely new dimension of beauty to the garden.