Growing Sunflowers

How to Plant, Grow, and Care for Sunflowers

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Sunflowers say “summer” like no other plant. Native to North America, sunflowers are heat-tolerant, resistant to pests, and simply beautiful. You can even harvest their edible seeds. Here’s how to grow them in your garden!

An annual plant, sunflowers have big, daisy-like flower faces of bright yellow petals (and occasionally red) and brown centers that ripen into heavy heads filled with seeds.

Sunflowers are heliotropic, which means that they turn their flowers to follow the movement of the Sun across the sky.

Tall and coarse, the plants have creeping or tuberous roots and large, bristly leaves. Some sunflowers grow to over 16 feet in height, though there are also varieties today that have been developed for small spaces and containers.

Most sunflowers are remarkably tough and easy to grow as long as the soil is not waterlogged. Most are heat- and drought-tolerant. They make excellent cut flowers and many are attractive to bees and birds.

Learn more about why you should start growing these happy flowers in your garden.

Planting

Choosing & Preparing a Planting Site

Sunflowers grow best in locations with direct sunlight (6 to 8 hours per day); they require long, hot summers to flower well.
Sunflowers have long tap roots that need to stretch out, so the plants prefer well-dug, loose, well-draining soil; in preparing a bed, dig down 2 feet in depth and about 3 feet across to ensure the soil isn’t too compact.
Find a well-drained location, and prepare your soil by digging an area of about 2-3 feet in circumference to a depth of about 2 feet.
Though they’re not too fussy, 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, put seeds in a spot that is sheltered from strong winds, perhaps along a fence or near a building.
Before planting, decide whether or not you want to grow a fun sunflower tower.

Sunflowers

Planting Sunflower Seeds

It’s best to sow sunflower seeds directly into the soil after the danger of spring frost has passed. Ideally, the soil temperature has reached 55 to 60 degrees F (13–16°C).
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.)
Plant the large seeds no more than 1 inch deep about 6 inches apart after the soil has thoroughly warmed, from mid-April to late May in northern regions—earlier in southern areas. You can plant multiple seeds and thin them to the strongest contenders when the plants are six inches tall.
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.

Care

Caring for Sunflowers

While the plant is small, water around the root zone, about 3 to 4 in. 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.

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.
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

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

To harvest seeds, keep an eye out for ripeness. The back of the flower head will turn from green to yellow and the bracts will begin to dry and turn brown; this happens about 30 to 45 days after bloom and seed moisture is about 35%. Generally, when the head turns brown on the back, seeds are ready for harvest.
Cut the head off the plant (about 4 inches below the flower head) and remove the seeds with your fingers or a fork.
To protect the seeds from birds, you can cover the flowers with a light fabric (such as cheesecloth) and a rubber band.
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.

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.
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.”

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

Cooking Notes

Sunflowers are one of the most important oil crops in the world, and are a valuable food source in many countries. 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.
For eating, the seeds must be dried on the plants. Rub the seeds off and soak them overnight in a gallon of water to which a cup of salt has been added, then dry them again in an oven at 250 degrees F for 4 to 5 hours. Store them in an airtight container.
One 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.

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Reader Comments

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Sunflowers drying up - look dead

I bought 2 Sunflower plants at Home Depot. They looked great with lots of flowers. I planted them in a flower box- plenty of sun. The flowers almost immediately dried up and the new flowers look dead as soon as they appear. I have watered liberally (thinking they were too dry) and it has not helped. Any thoughts for me? Thanks

Sunflowers drying up

Mine are doing the same thing! I bought mine at Home Depot also! The leave are withering. Someone please help!

you have a years warranty on

you have a years warranty on home depot plants! Take them back!

Can a sunflower that got broken off near the ground be saved?

Had a sunflower get broken off in a storm yesterday. Is there a way to save it?

sunflower stalk

If the sunflower stalk is just broken and bent, you could try to splint the stalk against a popsicle stick or a BBQ skewer. Gently wrap the stalk to the support where the break in the stem is located to see if the stalk can be cured. If it’s clearly cut off, cut the stalk cleanly to just above some leaves on the stalk and it might grow up with a lot of sunflower heads.

Sunflower

This happened to me and the leaves immediately withered. I used band aid plasters around the break, fed and watered it and it recovered brilliantly. I continue to water it well and it is thriving.

Sunflowers

I enjoyed your article on Sunflowers, which are my favorite after Zinnias. I would love to have big patches of sunflowers, but my problem is CHIPMUNKS.. I have tried everything I know to do, and the stinking things still get at the seeds or seedlings. I even tried planting them in seed trays, but they never get that big, or robust as they get from being planted directly in the ground. I left piles of bird seed from my parrots cage, hoping to distract them, but they got the leftovers, along with the seeds. I tried netting over the ground, and they dig right under the netting. I even tried planting the seeds & putting mothballs near the seeds, and they dig em out anyway. I am at my wits end. Those stinking chippys don't bother anything else.

sunflowers/chipmunks

i love both chippys and sunflowers! I solved your problem by bribing them with peanuts. we have an agreement!

I am thankful that I've found

I am thankful that I've found this site...very informative and helpful. I am a sunflower lover too and have been trying (for three years now) to sustain growing my sunflowers (in pots) but always fail after some weeks...I found it out now what's lacking...many thanks and God bless :)

Who is the author of this

Who is the author of this article and what year what this article last edited?

HOW CAN I GET THE OIL PLEASE

Please, how can i get the oil?

Making sunflower oil

Sunflower oil is awesome. Very healthy. To make cooking oil, you need to use the black seeds, not the confectionary seeds you find in the supermarket and you also need a mechanical press. Typically, it takes about 28 to 30 pounds of seed to make a gallon of oil. After the sunflower heads fall over, harvest the seeds. You just cut off the head of the sunflower plant with a knife and shake the seeds into a bucket. Dry your seeds first on a baking sheet or wood for a day in the sun. Don’t let the birds get those seeds! Then you take the press to crack your seeds. This is manual and a lot of cracking! About 20 minutes of cracking gives you a (two-liter) soda bottle’s worth of pressed sunflower seeds which provides about 12 ounces cooking oil. Pour the sunflower oil into mason jars and screw the lid on firmly. Store in the cupboard shelf until ready to use. The oil should be viable for at least two years.

red

The base of my sunflower is a deep red, but then it changes into a green stem! I don't think it's stressed because I have a second one growing just fine. Other things are it's growing tall without growing very many leaves, it's growing very slowly, and, of course, the stem is red and green. Thank you for helping.

they grow and blossom also in fresh manure

I live in the subtropics and use sunflowers to start a new vegetable bed. Amazingly easy to grow! I mix 2 parts fresh cow manure (so not composted!) with 1 part dirt and as many leaves I can find. I throw the cheap seeds (for parrots) simply on top and 1 -2 inches of mowed grass as mulch over the seeds.
Amazing, in one week the first leaves appear. The plant are great to provide shade as soon as the soil is ready for the vegetables like pumpkin or beans etc. By then they are tall enough for the young veggies to be protected against the burning sun.

Just wanted to write this idea for others who live in harsh conditions of sun as well.

Sunflower

Could a red sunflower survive being re-potted every once in a while? i have one I am growing indoors

Re-pot sunflower

Sunflowers can be transplanted but you need to be careful to dig far away from the roots so that you don’t cut or damage them. When replanting, make sure the soil is loose and not too compact so the roots can breathe. Plant at the same depth. Tamp down the soil at the soil line and water deeply.

Pests

A neighbor told us that sunflowers attract stink bugs. Is that true?

I cut down my sunflowers

I cut down my sunflowers yesterday and they were covered in stink bugs. I’m not sure if it was I because it was so muggy and humid yesterday so they were taking shade from the sunflowers or if had been like that all the time, but they were covered. I just flicked them off.

sunflowers and pests

Sunflowers are most definitely not pest resistant! I've planted them 3 times this summer alone, because the little ones keep being eaten. There are holes in the leaves of 90% of the ones that are still alive, and one is on its last leg, all but the central tiny leaves being chewed up.

Sunflower

I just planted them 1/2 acres I live in La. in Washington parish 70438 will and how long will it take to bloom

Replanting

Hi! Can anyone tell me how soon after harvesting the seeds can they be replanted? I’ve tried some directly off the plant and a couple days dry, but nothing. It’s nuce and warm here and other starts are doing great! So, how long do I wait? Does it have to be a whole season? Thanks!

Replanting

Did you ever find an answer to your house soon sunflower seeds can be replanted? I have the same question

Shocker

I love your picture

sun flowers & growing cooking apples

thank you and to your company for the excellent advice on both projects

sunflower

sunflower growing well school project but has not produced a flower why

Sunflowers without flowers

If this is a school project, the main reason for lack of flowers it that your sunflowers aren’t getting even full, direct sun.

Also, check your seed packet. How long does it say your variety will take to blossom? Sometimes, it’s longer than you realize. Also, we had a cool late spring in most regions, so if you planted your seeds late, it may be a few more weeks before you see buds.

Sunflowers

Should you remove the small grown leaves at the base of other leaves as you do with tomato plants;?

Pinching Sunflowers

No, these leaves will turn into full size leaves as the sunflower grows taller. Pinching is generally only done with young sunflowers, and is done to the main tip of the plant. This encourages them to branch out and produce more blooms.

Help I think my son's sunflower is dieing

My 6 year old son was given a sunflower seed from his school to grow back in April, basically at the end of the school year all the kids have a photo taken with their sunflower and who ever grows the tallest sunflower wins a prize.

Up to now it has been growing very well. Now all the leave along the stem have turned brown with the exception of some new leaves growing up at the top of the plant.

Unfortunately for my son I have a terrible history of looking after plants, so I am not his best helper. Amazing how I am able to keep my kids alive but not a plant... who figures hey :-)

Anyway just wondering whether this plant can be revived or I have I successfully helped to kill off another plant ..

brown leaves

As they grow, sunflowers normally drop some of the lower leaves. This can happen with pests and diseases, too. Downy mildew can be a problem in waterlogged soils or during warm humid days with cool, damp nights; it shows up as white fuzzy growth under leaves and mottled pale areas on upper surfaces; eventually the leaves die, starting with older (lower) leaves. If you suspect this is the problem, let the soil dry out between waterings and improve air circulation. Water only at the soil surface; avoid getting the leaves wet. Your local garden nursery may be able to advise you on other control options, such as fungicides.

Other diseases can cause leaf spots, wilting, etc. Rust, with blisters underneath and black spots on top of leaves can sometimes be a problem. Certain conditions such as lots of rain or heat, may also cause stress. As long as the flower has some healthy leaves up top, though, it may be that, even with certain diseases, the plant will live long enough for the flower to mature. Be sure that the plant is getting enough light and the proper amount of water; they can stand dry spells fairly well. Allow soil to dry before watering deeply and regularly.

Hope your son’s sunflower recovers and grows big and tall!