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.
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sunflowers in a container
they were gorgeous and we put them in a bigger pot in the sunniest place outside and they are now rapidly failing what could be the problem ???
Hardening Off
If they were moved from indoors directly to a sunny spot, they are likely suffering from the shock of too much light (and heat). Plants that are grown indoors need time to adjust to the intensity of the Sun’s rays outdoors, which is why hardening off seedlings is important. Additionally, when plants are transplanted, their roots are often damaged to some extent and need to settle in again. Before then, they are more vulnerable to stress from things like too much or too little water, or too much sunlight.
Stems what to do with them
My husband wants to know if he could till the stems into the garden?
Sunflower Stems
It depends on how big they are. If they’re from smaller, thinner sunflowers, then you could get away with tilling them into the garden and letting them compost on site. If they’re of the thicker variety, you’ll probably want to break them down yourself and compost them in a dedicated compost heap.
No seeds??
I planted several sunflowers this year. All of them grew to about 5-6' tall. Beautiful flowers! However, only half of the flowers had shells with seeds in them. The other half had the shells, but nothing inside. Any ideas to what was the problem??
Poor Seed Development
This could be due to insufficient pollination or, if it’ was particularly dry in your area this summer, a lack of sufficient water. Additionally, some varieties are better suited to developing “meaty” seeds. Generally, the large, “mammoth” sunflowers have the best seeds.
Great Article
This year is my first year growing sunflowers and I planted a whole variety of different kinds. About a third of the seeds I planted came up and are doing great! Most of my sunflowers respond heliotropically as you stated here, and have been blooming sporadically throughout the season. I love your idea about planting in rounds so they keep blooming through the fall (where I'm at they would probably be done by mid September). I did not do that this year, but probably will next year! Hoping to use seeds from this year's flowers to grow next year's :) Thanks for the good read and the insight!
Sunflowers do more for the land than look pretty
The reason I am here reading up on how to grow these is because these and hemp are both very good at removing toxins from the land. If someone wants to grow organic food but their land tests positive for chemicals not allowed in organic food, they can grow sunflowers or hemp and they will pull a vast number of harmful chemicals out of the ground and store them. I would not consume the seeds without having them tested for the chemicals first, but I just thought people might want to know that these are not only beautiful but they can serve a real purpose in healing the land.
Saving Seeds
I am growing sunflowers and want to harvest and save the seeds for next year. If I cut the heads and put them in water inside, will they continue "growing" and developing seeds, or do I need to leave the heads on the plant until the season is over? It would be nice to have beautiful flowers in the house, but I don't want to sacrifice the seeds.
seeds
As per above, for indoor bouquets, cut the main stem just before its flower bud has a chance to open to encourage side blooms.
For seeds,
large sunflower
We have an 18 footer that came up in the middle of the tomatoes this summer. I assume it was squirrel-planted. It towers over everything. I call it our personal jack and the beanstalk. had to support it with twine "guy wires" anchored to corners of the garden.
holes in the leaves
This is my first time growing sunflowers and they are doing well. They are from 5 to 7 feet tall and still growing. They have been fine up to about two weeks ago. They are now getting holes in the leaves, like something is eating them. Now I have found earwigs and small yellow flies on the plants. Do these help or hinder. What can I do?
Pest Eating Sunflower Leaves
Hi William,
It could be sunflower beatles or grasshoppers eating your sunflower leaves. However, once your sunflowers are that tall, there is no real worry of them harming the growth of the plants. The plants can survive and even thrive despite some foliage being eaten. We hope this helps!
Sunflowers and Wind
We garden in a very windy spot. This article says to avoid winy places for growing sunflowers, which is the one part of which I disagree. Sunflowers love the wind! Thanks to the wind, our sunflowers grow massive and impressive looking trunks like trees. A very few get knocked over when the soil is wet, and a hard wind comes through, but they just make up for it and grow stronger with a bend at the base. By the end of summer, the thick stems tower overhead like the canopy of a magnificent flower forest.
Sunflowers in Turkey
Back in 1986 & 1987 I was stationed in Turkey, the Country. We took a road trip and after passing the mountains surounding the capital we found ourselves driving through miles and miles of sunflowers. I asked a Turkish friend about them when we got back into town and was told that they harvested the heads for seeds and oil and the white pulp in the stems they used to fabricate Insulation.
Growing sunflower
This is fantastic, I love it.
Sunflowers molding?
Some have told me to cut the seed head off my monsters when birds start eating them. It's cold here and I didn't have alot of room in the house so I put them in paper bags (cut in 3-4 pieces each) and put them in the shed. The backs have turned black on some and some of the seeds have mold on them. Can they still be harvested and eaten? Do I need to bring them in where it's warmer or is it too late?
Moldy Sunflower Seeds
We would not advise eating the moldy seeds. They are also unhealthy for birds, so it’s probably best to toss them. Unfortunately, if the others were kept in the same bag, they may have mold spores on them despite looking alright.
Sunflowers
Planted six seeds this spring. Five survived and now are from eight to ten feet tall. One of them has a head about ten inches in diameter and drooping over. What, if anything do I do with it? My first time for Sunflowers. What do I do with them this fall?
3 headed sunflower
Hello. We have been stationed in Germany for almost a year. I decided to buy some bags of sunflower seeds for the birds and one of the seeds germinated in my flower bed. I left it alone to see if it would grow. It is now approximately 4 feet tall. The interesting thing is that it is one stalk with 3 flower heads on it. Is this a normal thing? One head is now opened, second is half opened and 3rd is just starting to open. I can send a photo if you need to see it.
Multi-Headed Sunflower
Yes, this is normal! Many sunflower varieties produce more than one flower, while others (typically the giant ones) only produce one.
Sun flowers
Planted year old seeds. Plants instead of growing leaves on the main stock new arms with leaves and very small flowers grow. First time this has happened to me. Plants are six feet tall now, and very bushy, four feet wide. Do you think I’ll get a big flower?
Sunflower
The plant isn’t likely to form a massive flower head, but you should get a terminal flower that’s larger than the smaller branching flowers. Unless the main stem was somehow damaged…? Sunflowers will branch out if damaged.
Planting Sunflowers
We got a small package of sunflowers in July to plant. Will they last until next year or should we go ahead and plant them now and try to retrieve some of the seeds for next year?
Sunflower Seeds
Sunflower seeds will last until next spring without issue, as long as they are kept in a cool, dry place.
Great Success
I have had great success with my Sunflowers. This year I tried growing a line of them on the Barn wall, it should look pretty. Sunflowers have a special meaning in our family and I do think the Sunny Flower is fun to grow. This year I tried some different varieties, the Lemon Sunflower and the Orange one.
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?
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