The sunflower -- a native American -- is the hottest garden flower going. Landscapers love them, kids crave them and flower arrangers seek them out in all their glory. Sunflowers are the toast of the country-living crowd -- even those who live in the city.
Although sunflowers were cultivated by the Incas centuries before the arrival of Europeans, we owe most of the recent developments in garden sunflowers to breeders from Europe, where the sunflower was introduced as early as the 1500s, and from Japan, where many of the latest cut-flower types were developed.
The genus Helianthus includes some perennials, but most of the sunflowers in today's gardens are members of the annual species H. annuus and H. debilis, or hybrids with one of these as the parent. I describe the two main types as stiff and relaxed, respectively.
Stiff varieties include the giant sunflowers that grace so many gardens and provide winter fare for birds. They are usually upright, with a thick, straight stem, large, coarse leaves and a large, solitary flower at the top. The blossom may be as much as 12 to 15 feet off the ground, and its nodding disk of large seeds a foot or more across. Less-common stiff types can range in height from a mere foot or two on up, and in some cases are freely branched and bushy, with many smaller blooms.
Relaxed sunflowers are rarely as tall as those grown for seed, and their multiple stems are less self-supporting, especially in windy gardens. The leaves are smaller and smoother, sometimes even velvety, and the many flowers are more reminiscent of a large black-eyed Susan (Rudbeckia), though the ray petals can be lemon yellow or even as pale as ivory.
The New Cut-Flower Types
Most gardeners only know one kind of sunflower, the golden yellow giants with stout stalks, short petals and a broad disk that, with the rapt attention of honeybees, becomes a full platter of plump seeds. But there are many other forms now available to American gardeners. In fact, one of the reasons sunflowers have become so fashionable is the incredible range of colors and types.
Shortest sunflowers. Perhaps the shortest sunflowers available, though they have full-sized flowers, are 'Sunspot' and 'Big Smile'. Odd as it may seem -- and it does to me -- these unique plants grow only one to two feet tall but bear full-sized blooms up to a foot across. Better proportioned, but still small enough to charm a child face to face, is 'Music Box'. This mix of colors ranging from creamy yellow to mahogany red is only three feet tall -- our kids love it.
Low growers. Only slightly taller, but aimed squarely at flower arrangers, are some of the latest European and Japanese varieties. 'Sunrich Lemon' and 'Sunrich Orange' are two well-named new hybrid sunflowers that grow only 30 to 36 inches tall and -- planted at the close spacing appropriate for cut-flower production -- produce uniform, black disk blooms that not only hold in the vase, but don't shed pollen on the table like old-fashioned sunflowers. The same is true of 'Sunbeam', with traditional golden yellow flowers and a unique green center that is very attractive. (Pollenless flowers are seedless if isolated from other pollen-producing varieties.) Similar, but slightly larger, is the pale yellow German cultivar 'Valentine', a personal favorite of mine. Other good midsized types are 'Sonja', a gold orange, and 'Floristan', an autumnal-colored mix, both of which are fine for cutting. A new, dark red cultivar is 'Prado Red'. All of these, because of their restrained size, will be at home in mixed bouquets.
Tall sunflowers. Next up on the size scale, growing four to eight feet tall, are a whole range of sunflowers that are useful both for cutting and for general garden and landscape use. Two choice cultivars are 'Lemon Queen' and 'Velvet Queen', five to six feet tall, with six-inch blooms. 'Velvet Queen' is a deep burgundy red with a black disk. 'Sol d'Oro' (called 'Sungold' in some catalogs) and 'Orange Sun' are a similar height, but fully double, with the ray flowers completely crowding out the disk and making the blossoms look like four- to six-inch pompoms.
At the high end of this middle range are the mixtures 'Autumn Beauty', 'Color Fashion', and 'Evening Sun', all of which grow six to eight feet tall and contain a wide and wonderful range of colors weighted toward the autumnal shades that are so attractive in the late-summer garden. Our favorite is 'Autumn Beauty', but all three are sure to please, especially if your garden is small and space is limited. One packet of seed will give you a hedge or a bountiful cutting.
What do modern breeders have in store over the next few years? Two things: They're working on more pollen-free varieties to make sunflowers a serious florist's flower (not a top priority on my list), as well as a whole range of new, pastel colors.
Sunflowers for Cut Flowers
Don't grow the cut-flower types of sunflowers as you do traditional kinds. First, you'll want to set aside a spot in the garden just for bouquet-making, a place where the flowers can be cut with abandon. Cutting gardens are better if separate from flower borders, where overall plant appearance, not yield, is the goal.
Second, skip the fertilizer and space the plants only six to eight inches apart -- at most. Rich soils and wide spacing are the bane of cut-flower types because pampering makes the plants grow much too large and produces flowers of such size that they are hard to use in a bouquet. Some commercial growers space their plants at only three to four inches! The plants themselves may not look like much, but the blooms will be beautiful, and just the right size for arranging.
Third, plant every two weeks for a continuous crop of flowers. Most of the cutting-type sunflowers will be ready for harvest just about 60 days from sowing (during the summer) but they don't last a long time, so you should replant every two weeks if you want a steady supply of blossoms for bouquets.
For maximum vase life, cut sunflowers just as the blossoms begin to open -- preferably the day before you need them. Harvest in the early morning, when the plants are still full of moisture from a night's rest. Immediately after cutting, remove all but the two or three leaves just below the blossom and plunge the stems directly in a bucket of water. A teaspoon of sugar per gallon of water will help the blossoms open fully. Change the water when you switch the stems to their final vase, as bacteria thrive in sugar water and will cause the blooms to deteriorate prematurely. Well-grown, promptly harvested, properly treated sunflowers will last 10 to 14 days.
Sunflowers for Cutting
Here are 35 varieties of sunflowers that make excellent cut flowers. Plant height and flower sizes are given as a range because, as the text explains, culture determines ultimate size. Most of these are stiff varieties; the relaxed types are noted with an asterisk. Descriptors are in this order: Name; plant height (in feet); flower diameter (in inches); and central disk color.
Mixed Autumnal Shades
Shepherd Ogden is a garden writer and the founder of Cook's Garden Seeds.
Photography by Suzanne DeJohn/National Gardening Association