Height is a symptom of conditions rather than a variety trait. Most disappointments trace back to crowding and to feeding at the wrong moment. In summer’s heat, it’s a huge relief to stand below towering sunflowers, shaded from the intense sunlight. These blooms are thequintessential flower of summer,and they’re pollinator powerhouses. They also offer seeds, which can be pressed into oil or butter, depending on your taste. If you’ve tried to grow them in the past but struggled to get them to grow, there are a few ways to achieve big stalks and giant flower heads. While it starts with picking the right type of sunflower, there are a few ways to care for them to promote even higher stems. Did I mention you can roast an entire giant sunflower head? Pretty wild, right? You have to be able to reach up and cut the head of the sunflower after it’s done blooming. After you retrieve it, let it dry in a protected area out of the elements.An airy outdoor space is best.Then remove the petals, season it up, and roast it.
Mongolian Giant Sunflower Seeds
Select Tall Varieties
To start, you need to plant the right kinds of sunflowers.The ‘ProCut®’ serieshas tall stems and decent-sized flower heads. ‘Sunzillas’ are also very tall, up to 16 feet, and they have large flowers. ‘Titans’ reach 14 feet at maximum height, and ‘Mammoths’ reach about 12 feet with up to one-foot-wide blooms.
‘Mongolian Giants’ are truly huge, reaching up to 15 feet and 18 inches across their flowers. If you’re unsure where to start, Botanical Interests has a few of these. You can also search for “hedge sunflowers”.This will get you to the tallest, towering sunflowersthe internet has to offer.
If you know a sunflower farmer, you can ask them for seeds. Chances are, they aren’t short on them, as each sunflower produces tons of viable seeds.
Space Appropriately
While you generally want to plant groups of multiple seeds every couple of feet when you’re starting your sunflowers,after they sprout, you should thin them.This gives them the maximum space and available nutrients to grow from a small sprout to towering sunflowers.
Sow your sunflowers directlyin the garden one to two weeks after your last frost. Once your sprouts reach a few inches tall, eliminate all but the most vigorous one in your newly planted hedge. Keep the sprouts after you thin them to eat. They’resome of the best sproutsout there, flavor-wise, and they’re full of nutrition. I like to throw mine on a salad or in a sandwich.
Feed Them
It’s really not necessary to feed sunflowers, but if your soil is lacking in richness and organic matter, it will help you grow towering sunflowers. Every month, either side dress your sunflower hedge withwell-rotted compost or apply an organic fertilizer.Liquids are faster to reach sunflower roots.
You don’t want to fertilize too much, as doing so promotes excess sugar production in plants. This attracts pests, which can hamper the growth of your sunnies.
Weed and Water
Weeding starts when you prep the bed. Remove weeds before you sow your sunflower seeds, and you limit competition for nutrients in the soil. Keep weeding throughout germination and continue to do so through the entire season. Water well, too.Sunflowers like somewhat moist soil.
Once they’re well established, you can cut back on watering. As you grow towering sunflowers, the leaves shade out the soil, and water evaporates from the surface less. Weeding is still important, even in later phases, but only add water if the soil is dry. When you water, do so deeply and slowly. Optimal conditions are present when you use soaker hoses or drip irrigation.
Provide Lots of Sun
They are called sunflowers, and therefore, they require tons of sunlight. When you pick a site foryour hedgeof towering sunflowers, ensure it’s not blocked by nearby structures, trees, or other plants. You wantplenty of sunlight from the get-go.At least six to eight hours ofdirect sunlightis a good baseline.
If you can, and if you need to, you can remove a branch or two from a tree to open your sunflowers up to more light access. If you’re in the northern hemisphere, plant them on the south side of your garden for the best results.
Scout for Pests and Diseases
While established sunflowers have no problem handling most pests and diseases, young sprouts are susceptible to plenty of problems. If youlook out for common pests and diseasesat this stage, you’ll be able to get your sunflowers to the mature, tall stage that you want them to get to.
Themost destructive pestsare weevils and stem borers. Look out for egg masses on the leaves and girdling stems. Check the crown of the plants for evidence of feeding at the root level. Look for darkening and sogginess. The disease of most concern is damping off.
As long as you have well-draining, fresh soil and you water appropriately, this is less likely to take hold. But it causes seedlings to suddenly die. If yours die back unexpectedly,try to sow more seeds in another area.As long as you have a few months left in the season, you should be able to grow more of them in time.
Key Takeaways
So remember, it’s not hard to grow towering sunflowers, but there are a few ways you can ensure that your hedge is tall and lovely at the height of summer.
