Growing Sunflowers

How to Plant, Grow, and Care for Sunflowers

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With bright blooms that go from mid-summer to early fall, sunflowers say “summer” like no other plant. Our Sunflower Growing Guide covers everything from planting to cutting flowers to harvesting seeds!

Sunflowers (Helianthus annuus) is an annual plant with a large daisy-like flower face. Its scientific name comes from the Greek words helios (“sun”) and anthos (“flower”). The flowers come in many colors (yellow, red, orange, maroon, brown) but they are commonly bright yellow with brown centers that ripen into heavy heads filled with seeds.

Here and yonder, high and low,
Goldenrod and sunflowers glow.
–Robert Kelley Weeks (1840–76)

How Long Do Sunflowers Take to Bloom?

A fairly fast-growing flower, most sunflower varieties mature in only 85 to 95 days. The largest sunflower varieties grow to over 16 feet in height, while smaller varieties have been developed for small spaces and containers and rarely grow larger than a foot tall! The flower heads can can reach over 12 inches in diameter within the large seeded varieties.

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.

Very few plants are as heat-tolerant, resistant to pests, and simply beautiful. Sunflowers make excellent cut flowers and many are attractive to bees and birds.

At the end of the season, it’s easy to harvest sunflower seeds for a tasty snack or for replanting (see instructions below). Learn more about why you should start growing these happy flowers in your garden.

Planting

When to Plant Sunflowers

It’s best to sow sunflower seeds directly into the garden (or outdoor containers) after the danger of spring frost has passed anytime after soils have warmed to 50°F.
In most regions, this will fall between April and mid-July. In the south, this will probably occur in mid-March or early April.

Choosing & Preparing a Planting Site

Find a sunny spot! Sunflowers grow best in locations with direct sunlight (6 to 8 hours per day); they require long, hot summers to flower well.
Choose a location with well-draining soil. It shouldn’t pool water after it rains.
Sunflowers aren’t picky but the soil can’t be too compact. They have long tap roots that need to stretch out; in preparing a bed, dig down 2 feet in depth and about 3 feet across.
They’re not too fussy when it comes to soil pH either. Sunflowers thrive in slightly acidic to somewhat alkaline soil (pH 6.0 to 7.5).
Sunflowers are heavy feeders, so the soil needs to be nutrient-rich with organic matter or composted (aged) manure. Or, work in a slow release granular fertilizer 8 inches deep into your soil.
If possible, plant sunflowers in a spot that is sheltered from strong winds, perhaps along a fence or near a building. Larger varieties may become top-heavy and a strong wind can be devastating.
Before planting, decide whether or not you want to grow a fun sunflower tower.

Sunflowers

Planting Sunflower Seeds

Sunflowers should be planted 1 to 1-½ inches deep and about 6 inches apart after the soil has thoroughly warmed. If you wish, you can plant multiple seeds and thin them to the strongest contenders when the plants are six inches tall.
Give plants plenty of room, especially for low-growing varieties that will branch out. Make rows about 30 inches apart. (For very small varieties, plant closer together.)
A light application of fertilizer mixed in at planting time will encourage strong root growth to protect them from blowing over in the wind.
Experiment with plantings staggered over 5 to 6 weeks to keep enjoying continuous blooms.
If you see birds scratching around for the seeds, spread netting over the planted area until seeds germinate. See more ways to keep birds away from your garden.

Check out this video to learn how to plant sunflowers:

Care

Caring for Sunflowers

While the plant is small, water around the root zone, about 3 to 4 inches from the plant. To protect the plant, it may help to put snail or slug bait around the stem.
Once the plant is established, water deeply though infrequently to encourage deep rooting. Unless the weather is exceptionally wet or dry, water once a week with several gallons of water.
Feed plants only sparingly; overfertilization can cause stems to break in the fall. You can add diluted fertilizer into the water, though avoid getting the fertilizer near the plant’s base; it may help to build a moat in a circle around the plant about 18 inches out.
Tall species and cultivars require support. Bamboo stakes are a good choice for any plant that has a strong, single stem and needs support for a short period of time.

Red sunflower. Photo by Chris Burnett

Pests/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.

Harvest/Storage

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.

Dried sunflower heads

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! Read all about harvesting sunflowers here.

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.

Learn how to roast seeds in the cooking notes below.

Recommended Varieties

Everyone is familiar with the huge sunflowers that grow on towering eight-foot-tall stalks. But did you know that some varieties top off at a modest 15 inches?

The towering ‘Mammoth’ variety is the traditional giant sunflower, sometimes growing to more than 12 feet tall. Its seeds are excellent for snacks and bird feeders, too.
‘Autumn Beauty’: One of the most spectacular cultivars, the ‘Autumn Beauty’ has many 6-inch flowers in shades of yellow, bronze, and mahogany on branching stems up to 7 feet tall.
‘Sunrich Gold’: A great flower for bouquets and arrangements, this sunflower grows to be about 5 feet tall and produces a single 4- to 6-inch flower. The big, no-mess, pollenless flowers have rich, golden-yellow rays and green-yellow centers.
‘Teddy Bear’: Just 2 to 3 feet tall, this small sunflower is perfect for small gardens and containers. The fluffy, deep-gold, 5-inch blossoms last for days in a vase.

Wit & Wisdom

Some people call sunflowers the “fourth sister,” in reference to the Three Sisters: corn, beans, and squash.
Some cultures see sunflowers as a symbol of courage.
Sunflowers were not only used for cooking by Native Americans, but also for healing (the oil was used to cure skin ailments) and making clothing (yellow dye was made from the flower petals and black or blue dye from the seeds).
Need a bird feeder? Save whole, dry sunflower heads and set them out in winter. Birds will gladly pick at the delicious seeds!
Save thick sunflower stems and dry them for winter kindling.
An anonymous buyer paid over $39 million in 1987 for Vincent van Gogh’s Sunflowers.
The tallest sunflower ever recorded was grown in Germany in 2014. It measured in at a stunning 30 feet and 1 inch tall!
Kansas is “The Sunflower State.”

Cooking Notes

Just one ounce of sunflower seeds contains about 6 grams of protein and 14 grams of oils. The fats are almost entirely unsaturated with 9g of polyunsaturated and 3g of monounsaturated fats per ounce (NSA). The oil is high in linoleic acid and is a good source of vitamin E.

Some varieties produce small black seeds that are used in cooking oil, margarine, cosmetics, and animal feed; they are the best sunflower seeds for attracting the greatest variety of songbirds.
The bigger, striped seeds are grown for snacking and as an ingredient in bread and health foods. They, too, are used for feeding birds, especially larger species, such as jays and mourning doves.

How to Roast Sunflower Seeds

Re-soak seeds overnight in salted water. Run through a strainer and dry on a layer of paper towels.

Bake for 25 to 30 minutes at 325 degrees on a baking sheet. Seeds should be spread out in a single layer. Stir frequently during the baking and remove seeds when they look slightly browned. Don’t burn!

That’s it! You can all some olive oil, salt, spices to your roasted seeds if you wish.

Or, you can also make suet cakes for the winter birds! See how to make suet.

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Reader Comments

Follow Up Question

So it has survived, and 2 new stalks appeared like any other pruned plant.
So followup up question is this, it appears to be tracking the sun does this mean it'll get heads or would plant do that anyhow? I've never grown sunflowers so I have no clue what to look for (likely too early to see new heads anyhow).
Thanks

Sunflower Head

Glad to hear there is more growth, however it is still unlikely there will be more blooms. It takes a lot of energy for the plant to grow the flower head, so if it was cut off prematurely, there isn’t enough energy to complete the task twice. The sun tracking is normal behavior for all plants and isn’t an indication of blooms. However, nature is astounding in many ways, so don’t give up on that flower yet!

Mother's day gift

My daughter's first grade class planted sunflower seeds in Styrofoam cups for mother's day gifts. My plant is appx 12 inches in height but saggy. I think the roots might have been water logged. I poked holes in the bottom of the cup today and lightly watered it and placed by a window. Is the sagginess normal when they are still little?
Also, I live in south Texas where there's plenty of sun and heat. Could I transplant to a pot or must it be in the ground?

transplanting sunflowers

It sounds like you need to get your sunflower out of its cup. You can plant the sunflower in a big, deep pot. The taller sunflower varieties also get top heavy and may start leaning. If you grow them in pots you may need to support the stalks against a wall or a fence.

Advice please. My 5 year old

Advice please. My 5 year old son was given sunflower seeds from school in pot. Grew in south facing kitchen window sill. They are now approx 18 inches in height. There are 2 gorwing in pot. When should I plant outside bearing in mind we live on the North East coast of England. (Tyne & Wear) feel free to google.

Planting out sunflowers

Mark you can plant out your sunflowers now if you put something over them to protect against the wind and frost.
I planted mine out 2weeks ago under a mini Polly tunnel they are doing really well and i live on the North Norfolk coast.

setting up stakes and braces for my sunflower crop

i am going to set up rows of stakes and string across the plot sturdy line for the plants to lean on as they grow. i know many taller sunflowers really need this type of help, but maybe the shorter ones will enjoy this same type of help. i really have enjoyed this forum so i hope i can refer back to you with progress reports on the SUNFLOWER PATCH i have got just about ready to plant i just wondered that birds can just easily dive down and peck up my seeds even before they sprout. i guess i have to drape netting over my plot too. who has had a strong crop before of sunflowers and how did you set the plot up for them?

Sunflower

It is a good article for beginners. Some highlight may be referred for special care.

All information about your flowers is so helpful!

Thank you for the great information on all your flowers!

have to move

I've been feeding the wild birds where I live sunflower seeds in a feeder. I read somewhere that you shouldn't stop feeding birds once you start feeding them. I have to move so should I plant some sunflowers for them so that they can eat the seeds? I'll feed the birds where I move to, but I'm worried about the ones that I feed now.

for the birds

You are a generous and thoughtful soul! These are lucky birds. There is only so much you can do. Planting sunflowers is a nice idea, but remember they are annuals and will be available only for one season. (They may self-seed but that’s not nec guaranteed.) You could leave the feeder for the next resident and, maybe, some seed, with instructions and best wishes. You could pass the feeder/seed on to a neighbor or friend in the vicinity. Other than that, depart with the understanding and assurance that you provided great relief and support to the birds.

Sunflower seeds and apartment living

I've just received sunflower seeds in memory of a friend but it's the last month of summer (I live in Melbourne, Australia) and I don't know if that's too late to plant them now. I have a north and east facing balcony that gets a ton of sun, so they could still fare okay in autumn. What do you think? I'm also wondering how to plant them in balcony pots. Sounds like they need a lot of room. Should I only plant one seed per pot or can you put a few in to see which seeds are the strongest and take? Thanks so much! This is a great thread.

sunflower memories

You have the right idea, Emily. You could plant them now and hope for the best. A few per pot, then eliminating weak ones is a good idea…but north and east are not the best Sun sides. As winter comes on, there will be less sunlight and less heat on the pot/plants. As for their needing a lot of room, some sunflowers do, yes—they can grow to a couple of meters in height! Or they can be knee high. The seed package should describe the plants at maturity. It’s also possible that you could save the seeds—or, say, half of them—and plant them next spring. If they are for this growing season, they may be fine a few months from now. Most seeds will last a year or so later than the package date. Put them in a cool, dry place and start them when danger of frost is passed. Start them indoors and transplant them outdoors, if you have space in the sun.

Sunny side

In Australia north is the most sunny side. Emily has sun all day.

Sunflowers to clean soil

I have about 3 acres of north facing hillside of a hollow that a neighbor has been dumping on. I have found automotive batteries, oil cans, and sadly, dead horses. There are some trees and some ferns but mostly just dirt and it is eroding. There is a year-round creek at the bottom and the area stays pretty moist throughout the summer.
I have read where sunflowers are being used to clean up radiation, lead, zinc, arsenic etc.. But I cannot find which strand would grow in these conditions. Hoping you can help me.

Sunflowers to clean soil

Oops. I mean strain not strand.

Sunflowers for Toxins

In addition to sunflowers, there are a few common plants that can help remediate soil toxicity. Given the degree to which your land has so sadly been abused, you might want to try planting a few different species. Alpine pennycress, Indian mustard, black mustard, and morning glory all absorb toxins in the soil. As for varieties of sunflowers, research is being done to determine if certain cultivars are more effective than others. You would do well to plant Helianthus annus ‘Mammoth’, which is a true sunflower. All the best with your admirable endeavors! We certainly hope you end up with a cleaner environment.

will it die?

i transplanted my sunflower so it could spread out its roots a little more but im worried it will die.

Transplanted Sunflower

True sunflowers are annuals. This is the time of year when they die back. Consider saving some of your plant’s seeds to grow next spring. Don’t fret, sunflowers are easy and quick to grow! (In general, sunflowers don’t take kindly to transplanting so try to pick a prime spot when first planting.)

I`m confused

well i transplanted it and it has been doing well it is even starting to bud

Date for the Article

I'm missing the date of publication too, please advise.

This article is by The Old

This article is by The Old Farmer’s Almanac. It is a Web article constantly updated, so there is not a date as you’d find in a printed publication.

Author

Hi, perhaps I missed it, but who wrote the article above?

Sun Flowers

Can you save and plant the seeds in the spring? I've never have grown sun flowers before, but our flowers have taken off and got huge. My wife and myself were really impressed on how they grew. I never had any luck with flowers before, but these sun flowers have changed my mind on trying to grow more next season. Also if we can reuse the seeds to plant, when would be the proper time to plant the seeds? Any info or help you could provide will be greatly appreciated. Thank-You for your time.

Sunny Forecast

Hi, Rick: You most certainly can save sunflower seeds, although bear in mind that if your sunnies are a hybrid variety (vs. open-pollinated), they may not propagate well (true) or even at all. Dry them well on paper towels and then store in an airtight container (such as a jar) in a cool place. They can be sprouted next spring for best results, but planting directly into the ground can also work. See the info above for more answers, and good luck!

Mammoth sunflower with multiple heads

Its my first time growing a sunflower. I planted a mammoth sunflower in a container without knowing how big it could get. It seems healthy but isn't very tall (probably because of it being in a container) but its grown at least 20 buds all over! I thought it was only supposed to have one! Is this normal??? So far, the bud at the top bloomed a few days ago, and yesterday two more just below it bloomed and are smaller. None are nearly close to being huge but again, it's probably due to me putting it in a container. Any info or advice is greatly appreciated as I would love to plant sunflowers again, but right this time :)

Sunflower Variety

Given the fact that your sunflower didn’t get very tall coupled with the multiple buds, we wonder if you inadvertently ended up with a dwarf variety. The very tall sunflowers typically have just one flower per stem, whereas many of the shorter varieties have many flowers and growing in a bushier form. When you plant next year, be careful about your seed source.

How to store seeds for next year

Hello, any recommendations on how to store sunflower seeds if we are planning on using them next year to plant?

Storing Sunflower Seeds

Hi Andy, First, you can leave sunflower heads on the plant as the seeds start to try. When the top of the blossom separates from the seed (or, the birds start eating the seeds), cut the head and finish curing the seed in a warm, ventilated area. Once the seeds are dry, store in an envelope or container in a cool, dry place where they are protected from insects.

sunfiower agri

i want growth the sunflower agriculter please send method .and what benifit treading