Updated: Apr 4
Helianthus is a genus comprising about 70 species of annual and perennial flowering plants in the daisy family Asteraceae commonly known as sunflowers. Except for three South American species, the species of Helianthus are native to North America and Central America.
Sunflowers are heliotropic, which means that they turn their flowers to follow the movement of the Sun across the sky east to west, and then returns at night to face the east, ready again for the morning sun. Heliotropism happens during the earlier stages before the flower grows heavy with seeds.
Table of Contents
6 - 10 feet ( Standard sunflower )
15 - 20 feet ( Giant sunflower )
1-3 feet wide
4.0 - 4.8
Growth Nutrition of Sunflowers
When it comes to the fertilization of sunflowers, nitrogen is extremely important. Fertilization of sunflowers with added nitrogen will contribute to the overall green growth of the plant. Fertilizing a sunflower with nitrogen will increase the height of the plant too.
Types of Sunflowers
Not all sunflowers grow to be the same size and color. Because of the several different species that occupy the Helianthus genus. It divided into three groups:
Because of their tall and rough stems, sunflowers can grow to be several feet high. Soaring to as high as 16 feet tall, these giant beauties are always trying to get their vibrant petals closer to the sun. The sunflowers that grow the tallest usually have big single stalks with large brown centers that connect to golden yellow petals.
Birds love tall sunflowers, because of their height and ability to produce a plethora of seeds in their centers. However, the bigger the sunflower, the bigger the responsibility, so be prepared to spend a lot of time and care on your flower if you want it to reach its maximum height. The most popular sunflowers of the tall variety:
Skyscraper - The Skyscraper sunflower rises high above the ground and can reach heights of up to 12 feet. These plants are held up by durable stalks and can produce 14-inch flower petals.
Sunforest Mix - This sunflower’s height can get anywhere from 10-15 feet high and 40 inches across. When planting these it is important to leave three to four feet between them so they have room to grow.
American Giant - Recommend sectioning off a corner of the garden for this one because this sunflower can grow up to 15 feet. With the long length off the stem and a face that grows to be about one foot in width, it is no wonder they call this sunflower the American Giant.
Russian Mammoth - This sunflower’s height ranges from 9 to 12 feet high and is used in a lot of county fairs and flower shows because of its size and effortless ability to grow. The Russian Mammoth lives best in a Mediterranean climate and can propagate as early as April.
Schweinitz’s Sunflower - This sunflower is one of the rarest species in America and is named after Lewis David von Schweintz a botanist who discovered the species in the early 1800s. Its average height is about 6.5 feet, but has been seen to grow up to 16 feet tall.
Most people like to think of sunflowers as tall beams not really suited for gardens. However, because of the increased hybridizing of these plant types, there are now a number of sunflowers that grow to heights of only three feet or smaller! Scientifically known as dwarf sunflowers, these plants love to grow in bunches and occupy small spaces such as gardens and planters.
Dwarf sunflowers have the same low maintenance care requirements as their taller family members and grow best when in full sunlight. Because of their smaller stalks, seeds only need to be placed three to six inches away. The most popular sunflowers of the dwarf variety:
Sundance Kid - One of the very first dwarf sunflowers to ever be domesticated, this flower grows anywhere between one to two feet tall. Reaching about knee high with bicolor red and yellow petals, this dwarf sunflower is truly one of a kind.
Little Becka - The average height of this pollenless sunflower is around one to two feet tall and can also be classified as a bi-colored sunflower because of its bright orange and red petals. The Little Becka looks great in gardens when wanting to add a little splash of color.
Pacino - The Pacino sunflower, also known as the “dwarf pacino gold,” usually grows to be about 12 to 16 inches with a maximum height of two feet. These sunflowers produce multiple heads on each plant and look great in large pots or planters.
Suntastic Yellow - Only getting to be about 20 inches tall, what these sunflowers don’t have in height they make up for in bold golden petals. The Suntastic Yellow likes to grow in packs of about five or eight and is perfect for gardens or bouquets.
Sunny Smile - Ranging from 12 to 15 inches tall, these miniature sunflowers bloom best in early to late summer. The Sunny Smile’s small size makes them extremely easy to grow, and their sturdy stalks are perfect when gardening with children or pets.
Just when you thought sunflowers couldn’t get any more beautiful, they now come in an assortment of colors thanks to hybridizing. You can now mix and match your favorite types and add splashes of color to your garden, patio or dining room table.
From creamy custard to deep red wine, here is a list of the most popular sunflowers of the colored variety:
Terracotta - The Terracotta is different from other colored sunflowers because instead of orange and red hues, it produces a more brown color on its petals. The brown clay color it possesses makes it ideal for fall displays.
Earthwalker - This flower is known for its dark earthy hues that can range between browns, reds and golds. The Earthwalker can grow anywhere between six to nine feet tall and is perfect for making a statement in the garden.
Ms. Mars - This striking flower has gorgeous red-to-purple hues that transform to a subtle yellow on the tips. They grow to be about two feet tall and look great in flower beds and borders.
Chianti - Without knowing this type of sunflower beforehand, one might not even recognize it. Arguably one of the darkest sunflowers in the species Helianthus, the deep red wine petals of the Chianti make it perfect for a dramatic contrast in any garden.
Moulin Rouge - No other sunflower quite matches the consistent, unique color the Moulin Rouge. Like its exotic name, this sunflower develops an extravagance of burgundy red petals that look fantastic in bouquets.
Here's how to choose the right spot and the right place for your plants.
Sunflowers are sun worshipers that grow best in spots that get six to eight hours of direct sun per day.
They have long tap roots that need to go several feet into the ground, so sunflower plants prefer loose, well-drained, somewhat alkaline soil with a pH of 6.0 to 7.5.
Sunflowers are heavy feeders, so they’ll be healthiest and generate the most blooms in nutrient-rich soil that has had compost or other organic matter mixed into it.
Growing sunflowers in pots is possible if you choose a smaller variety, like "Short Stuff" or "Teddy Bear." Be sure the pot is deep enough to accommodate their tap root.
If you’re growing one of the giant varieties that top 10 feet in height, plant them in a sheltered location or along a fence so they’re protected from the wind. Otherwise, a gust of wind could tip them over.
When to Plant Sunflowers
Plant seeds after the danger of spring frost has passed and the soil temperature is at least 60 degrees. This will be between March and May, depending on where you live.
You can get starter plants at a nursery or home improvement store, but growing sunflower plants is easiest if you grow them from seed sown directly into the ground. More varieties of sunflowers are available to you if you grow from seed. Growing sunflowers from seed is super easy, too.
How to Plant Sunflower Seeds
Plant the seeds no more than an inch deep and about 6 inches apart. Thin the seedlings once they hit 6 inches tall, leaving the strongest plants about 12 inches apart.
For continuous blooms, stagger your planting, sowing a new row of seeds every two to three weeks, beginning in the spring. Succession planting, as this is called, will keep you supplied with continuous blooms until first frost.
How long does it take for sunflowers to grow? From the time you put the seed in the soil to bloom ranges between 80 and 120 days, depending on the variety.
Caring for Sunflowers
When the plant is small, water the area around the roots, about 4 inches from the plants.
Once the plant is established, water deeply but infrequently to encourage the plant to grow deep roots. Water once a week with several gallons of water per plant, more often if the weather is very dry or very hot.
Tall varieties may need support so they don’t topple under the weight of their blooms. Bamboo or other types of wood stakes work well.
Pests and Diseases
Birds and squirrels will show interest in the seeds. If you plan to use the seeds, deter critters with barrier devices. As seed heads mature and flowers droop, you can cover each one with white polyspun garden fleece.
If you have deer, keep them at bay with a tall wire barrier. Curious deer may bite the heads off of young sunflowers.
Sunflowers are relatively insect-free. A small gray moth sometimes lays its eggs in the blossoms. Pick the worms from the plants.
Downy mildew, rust, and powdery mildew can also affect the plants. If fungal diseases are spotted early, spray with a general garden fungicide.
Cutting Sunflowers for Bouquets
For indoor bouquets, cut the main stem just before its flower bud has a chance to open to encourage side blooms.
Cut stems early in the morning. Harvesting flowers during middle of the day may lead to flower wilting.
Handle sunflowers gently. The flowers should last at least a week in water at room temperature.
Arrange sunflowers in tall containers that provide good support for their heavy heads, and change the water every day to keep them fresh.
Harvesting Sunflower Seeds
At the end of the season, harvest sunflower seeds for a tasty snack and or to replant or to feed the birds in the winter!
Let the flower dry on or off the stem until the back of the head turns brown, the foliage turns yellow, the petals die down, and the seeds look plump and somewhat loose.
With sharp scissors or pruners, cut the head off the plant (about 6 inches below the flower head). Place in a container to catch loose seeds.
Lie the sunflower head on a flat, clean surface and grab a bowl to hold the seeds.
To remove the seeds, simply rub your hand over the seeded area and pull them off the plant or you can use a fork. Another way to remove them is to rub the head of the sunflower across an old washboard or something similar. Just grip the head and rub it across the board as if you were washing clothes.
If you are going to harvest the seeds for roasting, you can cover the flowers with a light fabric (such as cheesecloth) and a rubber band to protect the heads from the birds.
Alternatively, you can cut the flower head early and hang the heads upside down until the seeds are dry; hang indoors or in a place that’s safe from birds and mice.
Rinse sunflower seeds before laying out to dry for several hours or overnight.
If you’re saving seeds to replant, store them in an airtight container in a cool, dry place until you are ready to plant.
Benefits of Sunflowers
Reduces risk of Cancer
Management of Diabetes
Boosts function of Brain
Helps in Weight Loss
Helps in Treatment of Anaemia
Helps to Detox our Body
Helpful During Pregnancy
Good for our Skin
Sunflower oil can be used in extremely high cooking temperatures and keep the food fresh and healthy for a much longer time.
To savor a tasty, healthy, and quick energy-giving snack, add sunflower seeds to any of your recipes.
They can be sprinkled over salads, cereals, soups, desserts, snacks, and can also be mixed with vegetables.
You can eat the seeds raw, roasted, or use them for flavor and texture in your selected recipes.